ACUS01 KWNS 071206
SWODY1
SPC AC 071204

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0704 AM CDT Sun Jun 07 2026

Valid 071300Z - 081200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST MONTANA...NORTHEAST WYOMING...AND THE WESTERN DAKOTAS THIS
AFTERNOON AND EVENING....

...SUMMARY...
Severe thunderstorms with damaging wind gusts, large hail, and an
isolated tornado threat are expected this afternoon and evening
across parts of the northern Plains. An isolated threat for
tornadoes and severe wind gusts will be possible across the Ozarks
region. Strong wind gusts will also be possible in the mid
Mississippi Valley and in the Mid-Atlantic.

...MT/WY/Dakotas...
A strong upper trough currently over the northern Great Basin will
translate eastward today, with large scale forcing for ascent
overspreading much of the northern High Plains region. This will
aid cyclogenesis over eastern WY and focus a surface cold front from south-central WY into northwest ND. Thunderstorms are expected to
form by mid-afternoon off the BigHorn mountains and build eastward
across southeast MT. While this environment will be post-frontal,
Relatively steep low-level lapse rates and moderate CAPE values will
support a risk of large hail and damaging winds.
Most CAM solutions suggest thunderstorms will become more numerous
and intense as they spread into western SD this evening, maintaining
support of the ENH risk area.

...Ozarks...
A weak cut-off low continues to drift northeastward across OK this
morning. An associated band of 30-40 knot southwesterly mid-level
winds and deep moisture will lie across the Ozark plateau today,
where scattered thunderstorms are expected through the period.
Parameters are rather weak across this region, but there will be
some risk of locally damaging wind gusts or a tornado this
afternoon/evening if pockets of daytime heating can occur.

...Eastern VA/NC...
A weak surface cold front is sagging southward across central VA
this morning. A combination of strong heating and frontal forcing
will lead to widely scattered thunderstorms this afternoon across
southeast VA and northeast NC. The strongest of these cells could
produce gusty winds.

..Hart/Wendt.. 06/07/2026

$$

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ACUS01 KWNS 071641
SWODY1
SPC AC 071639

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1139 AM CDT Sun Jun 07 2026

Valid 071630Z - 081200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST
MONTANA AND NORTHEAST WYOMING INTO NORTHWEST SOUTH DAKOTA AND
WESTERN AND CENTRAL NORTH DAKOTA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
WESTERN OZARKS...

...SUMMARY...
Scattered to numerous thunderstorms with significant wind gusts,
large hail, and an isolated tornado threat are expected this
afternoon and evening across parts of the northern Plains. A couple
of tornadoes and isolated damaging gusts are possible across the
Ozarks region.

...MT/WY/Dakotas...
Water-vapor imagery late this morning shows a strong upper trough
over the northwestern CONUS and it is forecast to pivot eastward
through the northern High Plains through tonight. Surface
mesoanalysis placed a low near the MT/ND/SD border with a frontal
zone draped southwest to northeast from northeastern WY into far
western ND. Cyclogenesis and strong heating/moistening of the
boundary layer will favor storm development by mid afternoon in the
vicinity of the Big Horns. Relatively steep low-level lapse rates
on the immediate cool side of the frontal zone and moderate CAPE
values will support a risk of large hail and severe wind gusts once
storms begin to mature. A linear cluster is expected to evolve
during the late afternoon into potentially a bow echo during the
early evening with the severe-wind risk notably increasing and
becoming more widespread. Have increased the intensity highlight
from southeast MT into western portions of ND where it seems
increasingly probable a swath of intense gusts ---possibly a bow
echo--- is progged by a diverse array of different model cores/runs
this morning. This model signal appears reasonable given the
co-location of surface features, lapse rates, and upper-level
support. It is within this mesoscale corridor that localized peak
gusts may range 85-100 mph. Considered an upgrade to Moderate Risk
but will defer to the 20 UTC outlook for additional model run-to-run
continuity and confidence in mesoscale environmental features. This
activity will sweep northeastward during the evening with a gradual
lessening of the wind/hail hazard towards the early overnight as it
moves east into the eastern half of the Dakotas late.

...Ozarks...
A weak trough/low over the central US with embedded disturbances
from OK into IA continues to drift northeastward late this
morning. An associated band of 30-40 knot southwesterly mid-level
winds and deep moisture will lie across the Ozark plateau this
afternoon. The 12 UTC Springfield, MO raob sampled this belt of
stronger flow with 80-kt at 200 mb. Heating of a very moist airmass
with some minor enlargement of low-level hodographs may result a few
weak supercells developing coincident with peak heating. A couple
of brief tornadoes and isolated damaging gusts are possible with
this activity.

...Eastern VA/NC...
A weak surface cold front is sagging southward across central VA
this morning. A combination of strong heating and frontal forcing
will lead to widely scattered thunderstorms this afternoon across
southeast VA and northeast NC. The strongest of these cells could
produce gusty winds.

..Smith/Chalmers.. 06/07/2026

$$

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ACUS01 KWNS 072001
SWODY1
SPC AC 072000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sun Jun 07 2026

Valid 072000Z - 081200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF SOUTHEASTERN MONTANA...EXTREME NORTHWESTERN SOUTH DAKOTA...WESTERN
AND CENTRAL NORTH DAKOTA,...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF
SOUTHWESTERN MISSOURI AND FAR NORTHWESTERN ARKANSAS...

...SUMMARY...
A bow echo with 60-100 mph gusts appears likely over the northern
High Plains into the Dakotas this afternoon, with a few instances of
severe hail and isolated tornadoes also possible. A couple of
tornadoes and isolated damaging gusts are still possible across the
Ozarks region.

...20Z Update...
A Category 4/Moderate Risk was introduced to portions of the
northern High Plains. Confidence is increasing in a well-defined cold-pool-driven bow echo MCS developing across portions of the
northern High Plains later this afternoon. A potentially dense swath
of 60-100 mph gusts appears likely, and a derecho may occur. Current observations depict a near stationary surface boundary across far
southeastern MT northeastward into western ND along an elongated
surface trough. High-resolution deterministic and ensemble guidance
(including HREF, REFS, and some of the latest WoFS runs) all depict
a classic bow echo MCS traversing this surface boundary, accompanied
by a widespread severe wind swath and scattered 75+ mph gusts. The
MCS would benefit from localized vorticity along this boundary,
which in turn could support book-end vortices and the subsequent
development and sustenance of a rear-inflow jet, lending
plausibility to the guidance consensus. Latest mesoanalysis also
shows continued eroding MLCINH and 2500+ J/kg MLCAPE in place. Low-
to mid-level lapse rates are already exceeding 8 C/km in some spots,
coinciding with 50-60 kts of sfc-8 km bulk shear oriented normal to
the anticipated bow echo leading line, which is favorable for
derecho development. Alternatively, multiple severe-wind producing multicellular clusters may occur, which would support higher
coverage of severe winds (with gusts occasionally exceeding 75 mph).


Otherwise, the previous forecast remains on track, with only minor
changes made to thunder and severe probabilities to reflect the
latest observations.

..Squitieri.. 06/07/2026

.PREV DISCUSSION... /ISSUED 1139 AM CDT Sun Jun 07 2026/

...MT/WY/Dakotas...
Water-vapor imagery late this morning shows a strong upper trough
over the northwestern CONUS and it is forecast to pivot eastward
through the northern High Plains through tonight. Surface
mesoanalysis placed a low near the MT/ND/SD border with a frontal
zone draped southwest to northeast from northeastern WY into far
western ND. Cyclogenesis and strong heating/moistening of the
boundary layer will favor storm development by mid afternoon in the
vicinity of the Big Horns. Relatively steep low-level lapse rates
on the immediate cool side of the frontal zone and moderate CAPE
values will support a risk of large hail and severe wind gusts once
storms begin to mature. A linear cluster is expected to evolve
during the late afternoon into potentially a bow echo during the
early evening with the severe-wind risk notably increasing and
becoming more widespread. Have increased the intensity highlight
from southeast MT into western portions of ND where it seems
increasingly probable a swath of intense gusts ---possibly a bow
echo--- is progged by a diverse array of different model cores/runs
this morning. This model signal appears reasonable given the
co-location of surface features, lapse rates, and upper-level
support. It is within this mesoscale corridor that localized peak
gusts may range 85-100 mph. Considered an upgrade to Moderate Risk
but will defer to the 20 UTC outlook for additional model run-to-run
continuity and confidence in mesoscale environmental features. This
activity will sweep northeastward during the evening with a gradual
lessening of the wind/hail hazard towards the early overnight as it
moves east into the eastern half of the Dakotas late.

...Ozarks...
A weak trough/low over the central US with embedded disturbances
from OK into IA continues to drift northeastward late this
morning. An associated band of 30-40 knot southwesterly mid-level
winds and deep moisture will lie across the Ozark plateau this
afternoon. The 12 UTC Springfield, MO raob sampled this belt of
stronger flow with 80-kt at 200 mb. Heating of a very moist airmass
with some minor enlargement of low-level hodographs may result a few
weak supercells developing coincident with peak heating. A couple
of brief tornadoes and isolated damaging gusts are possible with
this activity.

...Eastern VA/NC...
A weak surface cold front is sagging southward across central VA
this morning. A combination of strong heating and frontal forcing
will lead to widely scattered thunderstorms this afternoon across
southeast VA and northeast NC. The strongest of these cells could
produce gusty winds.

$$

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ACUS01 KWNS 080102
SWODY1
SPC AC 080100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Sun Jun 07 2026

Valid 080100Z - 081200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN NORTH DAKOTA AND FAR NORTHWESTERN SOUTH DAKOTA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHWEST
AND SOUTH-CENTRAL MISSOURI...

...SUMMARY...
A line of severe thunderstorms with wind gusts potentially above 75
mph is expected over the northern High Plains this evening, with
large to very large hail and an isolated tornado threat also
possible. A couple of tornadoes and isolated damaging gusts are also
possible in the Ozarks.

...Northern High Plains...
At mid-levels, an upper-level trough is moving eastward into the
northern Rockies. Further east, a lead shortwave trough is evident
on water vapor imagery over the northern High Plains. At the
surface, a 994 mb low is located in northwestern North Dakota with a
surface trough extending southward into northwestern South Dakota. A
cold front is in far western North Dakota. To the east of the front,
surface dewpoints are mostly in the upper 50s and lower 60s F, and
moderate instability is in place. Numerous thunderstorms have
recently developed to the west of the instability axis, and these
storms are expected to organize into an intense line segment over
the next couple of hours.

RAP forecast soundings in western North Dakota ahead of the storms
have 0-6 km shear in the 40 to 55 knot range, with 850 to 500 mb
lapse rates between 7.5 and 8 C/km. In addition, surface
temperature-dewpoint spreads exceed 25 degrees F over much area.
This environment will be very favorable for severe wind gusts. The
greatest potential for severe gusts will be from far northwest South
Dakota northeastward into much of western and north-central North
Dakota. Along this corridor, a nearly continuous bowing line is
expected to organize. Severe wind gusts above 75 mph will be
possible with the more intense segments. In addition to the
wind-damage threat, large to very large hail will be possible over
the next couple hours with storms that obtain supercell structure. A
tornado or two could also occur.

...Ozarks...
A mid-level trough will move northeastward across the central U.S.
this evening. Ahead of the trough, a moist and unstable airmass is
in place from the southern and central Plains eastward into the
lower to mid Mississippi Valley. Scattered strong thunderstorms are
ongoing along an axis of moderate instability over the Ozarks of
southern and central Missouri, where the RAP has MLCAPE in the 1500
to 2000 J/kg range. Ahead of the mid-level trough, low-level flow is
forecast to become maximized in the Ozarks over the next couple of
hours. Forecast soundings near Springfield, Missouri by 03Z have 0-3
km storm-relative helicity around 180 m2/s2. This will support a
tornado threat. A few strong wind gusts will also be possible.

..Broyles.. 06/08/2026

$$

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ACUS01 KWNS 080602
SWODY1
SPC AC 080600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Mon Jun 08 2026

Valid 081200Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...

...SUMMARY...
Scattered thunderstorms with large to very large hail, severe wind
gusts potentially above 70 mph, and a few tornadoes will be possible
today from the Front Range east-southeastward into the central
Plains. Isolated severe gusts and hail will also be possible in
parts of the southern High Plains, northern Plains and mid
Mississippi Valley. An isolated hail threat may develop toward the
end of the period in the northern High Plains.

...Front Range Into Central High Plains...
Southwesterly mid-level flow will be in place today from the
Intermountain West into the Great Plains. At the surface, a cold
front will advance southward across the central High Plains as a low
deepens ahead of the front. During the afternoon, an axis of
maximized low-level convergence will become focused along the Front
Range of east-central Colorado, along which thunderstorms are
expected in the afternoon. These storms will move eastward out of
the higher terrain into northeast Colorado during the mid to late
afternoon. A line of severe storms is expected to organize by early
evening.

RAP forecast soundings in northeastern Colorado late this afternoon
have MLCAPE peaking around 2000 J/kg with 0-6 km shear near 55
knots. 700-500 mb lapse rates are forecast to be around 8.5 C/km.
This will support supercells with large hail, and hailstones greater
than 2 inches in diameter will be possible with any rotating storms
that can become intense. In addition, 0-3 km storm-relative helicity
is forecast to peak around 200 m2/s2 over parts of northeastern
Colorado during the late afternoon, which will support a tornado
threat. As a cluster moves eastward into the central High Plains,
organization into a line is expected. This will increase the
potential for severe wind gusts, and a few gusts above 70 mph will
be possible.

...Great Plains...
A very moist and unstable airmass will be in place across the
southern and central Plains today, with surface dewpoints mostly
from the upper 60s F into the mid 70s F. This will enable a pocket
of strong instability to develop by afternoon across central Kansas.
From near the instability max westward, model forecasts suggest that
low-level convergence will become maximized during the afternoon
over parts of western and central Kansas. This should result in
isolated to scattered convective initiation. A cell or two is
expected to develop and move southeastward into the strong
instability during the mid to late afternoon.

RAP forecast soundings near the instability max at 21Z have MLCAPE
near 4000 J/kg with 0-6 km shear around 40 knots, and 700-500 mb
lapse rates near 8.5 C/km. This will be favorable for supercells
with large hail and severe wind gusts. Low-level shear may also
support a conditional and isolated tornado threat. In addition, the
strong instability will contribute to a potential for hailstones
greater than 2 inches in diameter and wind gusts above 70 mph with
the more intense rotating cells.

...Mid Mississippi Valley...
A mid-level trough will move northeastward today across the mid
Mississippi Valley. Ahead of the trough, an axis of moderate
instability is forecast from far western Kentucky into southern
Illinois. Along this axis, deep-layer shear is forecast to be
sufficient for an isolated severe threat. As low-level lapse rates
steepen in the late afternoon, a few severe wind gusts will be
possible.

...Northern High Plains...
An upper-level trough will move eastward into the western U.S.
today, as mid-level heights fall over the northern High Plains.
Ahead of the trough, a surface low will form in eastern Montana
tonight, as upslope flow develops to the east of the low. Near the
surface low, low-level convergence is forecast to become maximized
late in the period, which will support isolated thunderstorm
development from northeast Montana into far northwestern North
Dakota. Instability, deep-layer shear and steep lapse rates may be
sufficient for an isolated hail threat, mainly between 09Z and 12Z
Tuesday morning.

..Broyles/Supinie.. 06/08/2026

$$

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ACUS01 KWNS 081204
SWODY1
SPC AC 081203

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0703 AM CDT Mon Jun 08 2026

Valid 081300Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING FROM NORTHEAST COLORADO AND SOUTHEAST WYOMING INTO PARTS OF
NEBRASKA AND KANSAS....

...SUMMARY...
Scattered thunderstorms with large to very large hail, severe wind
gusts potentially above 70 mph, and a few tornadoes will be possible
today from the Front Range east-southeastward into the central
Plains. Isolated severe gusts and hail will also be possible in
parts of the southern High Plains, northern Plains and mid
Mississippi Valley. An isolated hail threat may develop toward the
end of the period in the northern High Plains.

...Eastern CO into Western NE/KS...
Relatively fast southwest flow aloft is present today from the
southwest states into the central Rockies. A surface low will
remain over southwest KS through the day, maintaining a stream of
easterly low-level winds and moist advection into eastern CO and
northwest KS. Daytime heating will further aid the westward
transport of moisture, resulting in an unstable air mass over the
foothills near Denver/CO Springs. Thunderstorms are expected to
develop in this corridor this afternoon, in an environment of steep
mid-level lapse rates, CAPE around 1000 J/kg, and favorable
deep-layer shear. Supercell structures capable of large hail will
be the main early threat. As this activity moves/builds eastward
into the Plains, it will encounter increasingly moist/unstable air
and strengthening low-level shear profiles by early evening. This
will promote a risk of a few supercell tornadoes, large hail, and
damaging winds. An upgrade to ENH risk may be needed in later
updates as clouds/daytime heating and affects of ongoing NE
convection is assessed.

By mid-evening, the activity is expected to be organizing upscale
into linear structures as it moves into southwest NE and northwest
KS. An increasing risk of damaging winds will likely develop, with
storms spreading eastward into the overnight hours.

...Northwest AR...
A cluster of intense thunderstorms is ongoing this morning over
southwest MO/northeast OK. This activity could continue to pose a
risk of isolated damaging wind gusts through the morning into
northwest AR before weakening later today.

...Southern KS/Northwest OK/TX Panhandle...
A dryline will become established this afternoon from the eastern TX
Panhandle to the surface low in south-central KS. Hot conditions
along/west of the dryline will help to initiate isolated
thunderstorms. These high-based cells could pose an occasional
threat of hail and damaging winds for a few hours.

...Eastern KS...
A moist and very unstable air mass will lie across eastern KS today
with CAPE values of 3000-4000 J/kg, but with a weak cap. CAM
guidance varies on the potential for afternoon/early evening
thunderstorms in this area, but enough 00z runs suggested a threat
to maintain the SLGT. Any storm that can form would pose a risk of
large hail and damaging winds.

...Southern IL/Western KY...
An upper trough continues to lift northeastward across the mid MS
valley today, with a moist/moderately unstable air mass present from
southern IL southward. Mid-level lapse rates are marginal for
severe storms, and winds aloft are modest. Nevertheless, veering winds-with-height and sufficient CAPE will pose an occasional risk
of strong storms capable of gusty winds or a tornado today.

..Hart/Wendt.. 06/08/2026

$$

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ACUS01 KWNS 081654
SWODY1
SPC AC 081652

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1152 AM CDT Mon Jun 08 2026

Valid 081630Z - 091200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
EASTERN COLORADO AND FROM NORTHERN INTO EASTERN KANSAS...

...SUMMARY...
Severe thunderstorms potentially capable of large to giant hail and
a couple of tornadoes are possible over the plains of eastern
Colorado. Scattered to numerous severe thunderstorms are possible
farther east over northern Kansas late this afternoon through the
late evening. Severe gusts ranging from 60-100 mph are possible
along with a risk for a couple of tornadoes.

...Eastern CO into Western NE/KS...
A belt of moderate southwesterly mid-level flow will be maintained
over the central High Plains to the downstream of a western U.S.
upper trough. A surface low near Dodge City, KS and moist easterly
low-level flow to its north, will contribute to upslope flow into
eastern CO and the CO Front Range. Strong heating and 50s to lower
60s deg F dewpoints and steep 700-500 mb lapse rates will result in
moderate to large buoyancy by mid afternoon. Elongated hodographs
will favor supercells with the more intense updrafts. Some increase
in low-level hodographs towards early evening coupled with a moist
boundary layer may aid in the risk for supercell tornadoes, in
addition to the risk for hail. Some of the latest model forecast
soundings suggest giant hail (3.0-4.5 inches in diameter) with the
more intense supercells over eastern CO late this afternoon into the
early evening. Severe gusts will also be possible with the stronger
storms with this activity diminishing by late evening.

...KS vicinity...
A very moist surface was analyzed this morning across the central
Great Plains to the south of a front across central and northern KS
to the east of a triple point. Model guidance shows lowest 100-mb
mean mixing ratios of 16-18 g/kg later this afternoon. This very
rich moisture coupled with heating to the south of the front and
early day outflow from storm activity over southwest NE, will result
in a very unstable airmass by late afternoon. Model guidance has
trended towards a severe MCS developing across northern KS and
moving east-southeastward into the lower MO Valley by late evening.
Although it remains unclear exactly how this will evolve, confidence
has increased with regard to a storm cluster and upscale growth
occurring on the northern rim of very rich moisture and a modest
southerly LLJ. Some indication exists for a couple of supercells to
develop ahead of the evolving cluster and eventual squall line.
Large hail and perhaps a tornado risk could accompany this activity.
Have increased severe-wind probabilities and intensity levels, with
the most intense phase of the squall line likely where the overlap
of greater effective shear (30-35 kt) and the large buoyancy
resides. A bow potentially capable of a swath of 60-80 mph gusts
(locally peaking 80-100 mph) is forecast, along with the possibility
for a couple of mesovortices capable of these locally higher gusts
and/or tornadoes. A gradual weakening is expected as this MCS moves
into western parts of MO late.

...Southern KS/Northwest OK...
A dryline will become established this afternoon from the eastern TX
Panhandle into south-central KS. Hot conditions along/west of the
dryline will help to initiate isolated thunderstorms. These
high-based supercells could pose an occasional threat of hail and
damaging winds for a few hours.

...Southern IL/Western KY...
An upper trough continues to lift northeastward across the mid MS
valley today, with a moist/moderately unstable air mass present from
southern IL southward. Mid-level lapse rates are marginal for
severe storms, and winds aloft are modest. Nevertheless, veering winds-with-height and sufficient CAPE will pose an occasional risk
of strong storms capable of gusty winds or a tornado today.

..Smith/Chalmers.. 06/08/2026

$$

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ACUS01 KWNS 081958
SWODY1
SPC AC 081957

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Mon Jun 08 2026

Valid 082000Z - 091200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF NORTHEASTERN COLORADO AND NORTHERN INTO CENTRAL AND EASTERN
KANSAS...

...SUMMARY...
Severe thunderstorms potentially capable of large to giant hail and
a couple of tornadoes are still possible over the plains of eastern
Colorado. Scattered to numerous severe thunderstorms are expected
farther east over northern Kansas late this afternoon through the
late evening. Very large to giant hail and severe gusts ranging from
60-100 mph are possible along with a risk for a couple of tornadoes.

...20Z Update...
Hail conditional intensity level 2, and tornado conditional
intensity level 1 were added to portions of northern into central
KS. Some of the latest high-resolution guidance depicts supercells
potentially remaining discrete or semi-discrete for a couple more
hours longer compared to earlier CAM runs. Given anticipated strong
low-level shear along the terminus of the low-level jet/baroclinic
boundary intersection, and over 40 kts of effective bulk shear
likely, any supercells that remain discrete could become quite
intense given strong to locally extreme buoyancy. Very large hail
approaching 4 inches in diameter may occur with longer-lived
supercells. Furthermore, RAP forecast soundings show appreciably
large and curved low-level hodographs this evening (given low-level
jet intensification). As such, a strong tornado cannot be ruled out,
either with discrete supercells or with a well-defined mesovortex as
storms merge into an intense cold-pool-driven bow echo MCS later
this evening.

A Category 4/Moderate risk was considered for this outlook. However,
it remains unclear whether supercells will rapidly grow upscale into
a bow echo, or maintain discrete structures for a longer period of
time. It therefore remains questionable whether significant-severe
hail or wind will dominate long enough to warrant Moderate risk
coverage of a specific hazard. Nonetheless, very intense and
damaging storms capable of a combination of all significant-severe
hazards are expected across portions of northern into eastern KS
this afternoon into the evening hours.

Otherwise, the rest of the previous forecast (see below) remains on
track, with only minor changes made to thunder and severe
probabilities to reflect the latest observations and guidance
consensus.

..Squitieri.. 06/08/2026

.PREV DISCUSSION... /ISSUED 1152 AM CDT Mon Jun 08 2026/

...Eastern CO into Western NE/KS...
A belt of moderate southwesterly mid-level flow will be maintained
over the central High Plains to the downstream of a western U.S.
upper trough. A surface low near Dodge City, KS and moist easterly
low-level flow to its north, will contribute to upslope flow into
eastern CO and the CO Front Range. Strong heating and 50s to lower
60s deg F dewpoints and steep 700-500 mb lapse rates will result in
moderate to large buoyancy by mid afternoon. Elongated hodographs
will favor supercells with the more intense updrafts. Some increase
in low-level hodographs towards early evening coupled with a moist
boundary layer may aid in the risk for supercell tornadoes, in
addition to the risk for hail. Some of the latest model forecast
soundings suggest giant hail (3.0-4.5 inches in diameter) with the
more intense supercells over eastern CO late this afternoon into the
early evening. Severe gusts will also be possible with the stronger
storms with this activity diminishing by late evening.

...KS vicinity...
A very moist surface was analyzed this morning across the central
Great Plains to the south of a front across central and northern KS
to the east of a triple point. Model guidance shows lowest 100-mb
mean mixing ratios of 16-18 g/kg later this afternoon. This very
rich moisture coupled with heating to the south of the front and
early day outflow from storm activity over southwest NE, will result
in a very unstable airmass by late afternoon. Model guidance has
trended towards a severe MCS developing across northern KS and
moving east-southeastward into the lower MO Valley by late evening.
Although it remains unclear exactly how this will evolve, confidence
has increased with regard to a storm cluster and upscale growth
occurring on the northern rim of very rich moisture and a modest
southerly LLJ. Some indication exists for a couple of supercells to
develop ahead of the evolving cluster and eventual squall line.
Large hail and perhaps a tornado risk could accompany this activity.
Have increased severe-wind probabilities and intensity levels, with
the most intense phase of the squall line likely where the overlap
of greater effective shear (30-35 kt) and the large buoyancy
resides. A bow potentially capable of a swath of 60-80 mph gusts
(locally peaking 80-100 mph) is forecast, along with the possibility
for a couple of mesovortices capable of these locally higher gusts
and/or tornadoes. A gradual weakening is expected as this MCS moves
into western parts of MO late.

...Southern KS/Northwest OK...
A dryline will become established this afternoon from the eastern TX
Panhandle into south-central KS. Hot conditions along/west of the
dryline will help to initiate isolated thunderstorms. These
high-based supercells could pose an occasional threat of hail and
damaging winds for a few hours.

...Southern IL/Western KY...
An upper trough continues to lift northeastward across the mid MS
valley today, with a moist/moderately unstable air mass present from
southern IL southward. Mid-level lapse rates are marginal for
severe storms, and winds aloft are modest. Nevertheless, veering winds-with-height and sufficient CAPE will pose an occasional risk
of strong storms capable of gusty winds or a tornado today.

$$

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ACUS01 KWNS 090107
SWODY1
SPC AC 090105

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0805 PM CDT Mon Jun 08 2026

Valid 090100Z - 091200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...

...SUMMARY...
Severe thunderstorms with large to very large hail, damaging wind
gusts and a couple of tornadoes are likely this evening from parts
of northeastern Colorado into northwestern Kansas. Large to very
large hail, severe wind gusts from 60 to 90 mph, and a tornado
threat are likely this evening across parts of north-central and
eastern Kansas. An isolated severe threat may persist for a couple
more hours from the eastern Texas Panhandle into northwestern
Oklahoma.

...Northeast Colorado/Northwest Kansas...
A mid-level shortwave trough, evident on water vapor imagery, is
currently moving northeastward across northeast Colorado. At the
surface, a front is located across eastern Colorado with a moist
airmass extending from northeastern Colorado southeastward into
western Kansas. Surface dewpoints along this corridor range from the
upper 50s to the mid 60s F, which is contributing to moderate to
strong instability. Scattered severe thunderstorms are ongoing
across northeastern Colorado along the western edge of the stronger instability, and further north into far southeast Wyoming and
western Nebraska. The storms are expected to organize into a line
and move east-southeastward into southwestern Nebraska and
northwestern Kansas this evening. Large to very large hail will be
possible with the more intense supercells over the next hour or two,
mainly along the southern end of the line where some cells are
likely to remain discrete. Hailstones up to 3 inches in diameter
will be possible. A couple tornadoes will also be possible with
supercells. As a transition to linear mode occurs, the wind-damage
threat will increase. Wind gusts above 75 mph will be possible near
the leading edge of any bowing segments.

...North-central and Eastern Kansas...
On water vapor imagery, a subtle shortwave trough appears to be
located from southern Nebraska southward into central Kansas. Ahead
of this feature, a pocket of strong instability is analyzed by the
RAP over south-central Kansas, where MLCAPE is estimated to be in
the 4000 to 5000 J/kg range. A line of severe storms is ongoing in north-central Kansas, to the north-northwest of the instability
maximum. Multiple supercells with potential for large to very large
hail are ongoing within this line. Over the next couple of hours,
this line is expected to organize into a bowing segment, moving east-southeastward across the remainder of north-central Kansas and
into eastern Kansas later this evening. The instability combined
with 30 to 40 knots of 0-6 km shear, and steep mid-level lapse rates
near 8 C/km will support a wind-damage threat. If a bowing line
segment can become intense later this evening, a potential will
exist for significant wind gusts above 80 mph. The wind-damage
threat will likely impact far eastern Kansas later this evening, and
western Missouri after midnight. A secondary line of thunderstorms
with severe wind gusts is expected to impact parts of north-central
Kansas after midnight.

...Eastern Texas Panhandle/Northwestern Oklahoma...
A very moist and unstable airmass is located across the southern
Plains. Surface dewpoints from the eastern Texas Panhandle into
northwestern Oklahoma are in the mid 60s to lower 70s F. This is
contributing to strong instability with the RAP showing MLCAPE in
the 3000 to 3500 J/kg range, with steep low-level lapse rates. The thermodynamic environment should support an isolated threat for
severe wind gusts for a couple more hours this evening...see MCD
1036.

...Far Western Kentucky...
A bowing line segment is currently ongoing in far western Kentucky
along an axis of moderate instability, where the RAP has MLCAPE near
2000 J/kg. RAP forecast soundings to the south of Paducah have 0-3
km storm-relative helicity around 200 m2/s2 early this evening,
suggesting that an isolated tornado threat may persist for another
hour or two. A few strong wind gusts will also be possible.

..Broyles.. 06/09/2026

$$

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ACUS01 KWNS 090556
SWODY1
SPC AC 090554

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1254 AM CDT Tue Jun 09 2026

Valid 091200Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL AND NORTHERN PLAINS...

...SUMMARY...
Numerous severe thunderstorms with a potential for 60 to 80 mph
winds with locally higher gusts, along with tornadoes (some
potentially strong), and large to very large hail are expected to
develop in parts of the central and northern Plains from this
afternoon into tonight. Severe wind gusts and hail will also be
possible from north-central and west-central Kansas southwestward
into the Texas Panhandle.

...Central and Northern Plains...
An upper-level trough will move eastward across the western U.S.
today. Ahead of the system, mid-level heights will fall over the
central and northern Plains. At the surface, a moist airmass will be
in place over the Great Plains, with a dryline located from far
western North Dakota southward into western Nebraska. To the east of
the dryline, surface dewpoints will be in the upper 60s and lower
70s F. As surface temperatures warm today, an axis of moderate
instability is expected to develop over the central Dakotas.
Thunderstorms will form near and to the east of the dryline in the
mid afternoon. Strong low-level convergence near the instability
axis will result in a relatively rapid transition to linear mode
with a large MCS expected to develop during the late afternoon and
early evening. The severe MCS will move eastward across the central
and eastern Dakotas, with the southern part of the line located in
central Nebraska.

Late afternoon RAP forecast soundings in the central Dakotas near
the instability axis have MLCAPE in the 4000 to 5000 J/kg range with
0-6 km shear between 30 to 40 knots. Low to mid-level lapse rates
are forecast to be in the 7 to 8 C/km range. This will be very
favorable for large hail and severe wind gusts. Hailstones greater
than 2 inches in diameter and wind gusts above 80 mph will be
possible with supercells early, and along the more intense parts of
the line as it develops.

Concerning the tornado threat, a mid-level jet will become
juxtaposed with a low-level jet in the late afternoon across central
and northern North Dakota. Storms that can remain discrete for a few
hours after initiation will have potential to become supercells and
produce tornadoes. The strongest low-level shear is forecast in
northeastern North Dakota, where RAP forecast soundings increase 0-3
km storm-relative helicity into the 250 to 300 m2/s2 range by early
evening. This will be favorable for a few strong tornadoes. Further
south from central South Dakota into Nebraska, there will be
potential for supercells with tornadoes near gaps in the line. The
threat for strong tornadoes may be greatest in the early to mid
evening as the line interacts with a 45 to 55 knot low-level jet
from far southeastern South Dakota southward into eastern Nebraska.

From late evening into the early overnight period, the severe threat
associated with the severe MCS is expected to gradually downtrend as
it moves into the upper Mississippi Valley.

...North-central and Western Kansas/Texas and Oklahoma Panhandles...

At mid-levels today, heights will fall within southwesterly flow
over the southern and central High Plains. At the surface, a moist
and unstable airmass will be located over much of the region. By
afternoon, a focused zone of maximized low-level convergence is
forecast to develop. This axis will move eastward toward the western
edge of the stronger instability, with thunderstorms forming in the
mid to late afternoon. Near the axis, MLCAPE is forecast to be
around 2000 J/kg with 0-3 km lapse rates near 8 C/km. In addition,
surface temperature-dewpoint spreads will be large, which will be
favorable for severe wind gusts in the late afternoon and early
evening.

...Upper Mississippi and Lower Ohio Valleys...
A mid-level ridge will move eastward toward the upper Mississippi
and lower Ohio Valleys today. Ahead of the ridge, moderate
instability will be in place by afternoon. Scattered thunderstorms
that form within this moist and unstable airmass will have potential
for isolated severe gusts, mainly as low-level lapse rates become
steep in the afternoon.

..Broyles/Thornton.. 06/09/2026

$$

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ACUS01 KWNS 091300
SWODY1
SPC AC 091259

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 AM CDT Tue Jun 09 2026

Valid 091300Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHERN AND CENTRAL PLAINS...

...SUMMARY...
Numerous severe thunderstorms with a potential for 60-80 mph winds
with locally higher gusts, along with tornadoes (some potentially
strong), and large to very large hail are expected across the
northern and central Plains this afternoon and tonight. Severe wind
gusts and large hail will also be possible from north-central and
west-central Kansas southwestward into the Texas Panhandle.

...Central and Northern Plains...
A prominent upper trough will shift east-northeastward from the
northern Rockies toward the northern High Plains and Canadian
Prairies through tonight, with height falls overspreading much of
the northern/central Plains toward the Upper Midwest. This will be
atop a moist airmass near/east of a dryline/front located from far
western North Dakota southward into western Nebraska. Warm sector
surface dewpoints will be in the upper 60s and lower 70s F.

Thunderstorms are expected to form near the front/dryline by
mid/late afternoon, initially spanning the west-central Dakotas
southward into western Nebraska. Some semi-discrete storms including
supercells may also form farther east within the warm sector,
enhanced as the mid-level jet phases with a significantly
strengthening low-level jet primarily focused across eastern North Dakota/northeast South Dakota. Aside from large hail, a few
tornadoes are expected, some of which could be strong especially
during the early/mid-afternoon hours. Over time and farther west,
strong low-level convergence near the instability axis will result
in a relatively rapid transition to linear mode with multiple linear clusters/possible MCS expected to develop by evening. The severe MCS
will move eastward across the central and eastern Dakotas, with
damaging wind and some hail/tornado potential continuing eastward
tonight toward Minnesota/part of Iowa.

Aside from North Dakota/northern South Dakota and northwest
Minnesota, another supercell/tornado-favorable zone could
materialize by evening farther southeast from southeast South Dakota
into eastern Nebraska and western Iowa/southwest Minnesota.
Mid-level temperatures will be a bit warmer and storm
coverage/certainty will likely be lesser across this region.
However, a rather favorable and potentially volatile environment
will exist as a secondary low-level jet branch increases and
interfaces with an effective warm frontal zone this evening, with
initial intense supercells plausible if/where storms develop.

...Western and central Kansas and Texas and Oklahoma Panhandles...
Higher-based storms are expected to develop regionally by late
afternoon/early evening with moderate buoyancy and very steep lapse
rates favorable for large hail and severe-caliber wind gusts, some
of which could be significant.

...Middle Mississippi Valley/Lower Ohio Valley...
As a byproduct of several decayed MCS, multiple MCVs will are
expected to drift east-southeastward across the region today and
interface with a moist/unstable environment influenced by outflow
and differential heating. A rejuvenated round of severe storms is
expected by mid/late afternoon, and some supercells are plausible if MCV-related mid-level flow diurnally persists. Multicells capable of
damaging winds are the most probable hazard, but some
supercell-related tornado potential may also exist.

..Guyer/Wendt.. 06/09/2026

$$

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ACUS01 KWNS 091637
SWODY1
SPC AC 091635

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1135 AM CDT Tue Jun 09 2026

Valid 091630Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN AND CENTRAL PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER
MISSISSIPPI VALLEY...

...SUMMARY...
Numerous severe thunderstorms with a potential for 60-80 mph winds
with locally higher gusts, along with tornadoes (some potentially
strong), and large to very large hail are expected across the
northern and central Plains this afternoon and tonight. Severe wind
gusts and large hail will also be possible from north-central and
west-central Kansas southwestward into the Texas Panhandle.

...Central and Northern Plains...
Current satellite imagery shows negatively tilted upper troughing
from the Pacific Northwest into the central Rockies, with an
embedded shortwave trough emerging over the northern/central High
Plains. This shortwave is forecast to continue northeastward today,
with associated height falls spreading from the northern/central
High Plains into the northern/central Plains and Upper Midwest.

Recent surface analysis shows a moist airmass across the Plains,
although notable airmass modification has occurred across KS and
western MO from an overnight MCS. Outflow associated with this MCS
currently arcs from south-central KS through extreme northeast OK
and southwest MO into south-central MO. Convective outflow also
exists over south-central NE. These features add to an already
complex surface pattern which features several lows along a wavy
surface trough from north-central MO into southeast CO. A stationary
boundary also extends northeastward from the low over southeast MT
through south/eastern ND and far northwest MN.

General expectation is for the north/central High Plains to eject
over the northern Plains, with the associated large-scale ascent and convergence along the cold front contributing to thunderstorms
across a large portion of the northern and central Plains. Very
strong buoyancy (i.e. MLCAPE over 2500 J/kg) will be in place across
much of this region, with potential pockets of extreme buoyancy
(i.e. MLCAPE over 4000 J/kg) from eastern SD through eastern
NE/extreme western IA. Thunderstorms are expected to form near the front/dryline by mid/late afternoon, along the western edge of the
greater buoyancy from the west-central Dakotas southward into
western Nebraska. High LCLs and more southerly deep-layer shear will
favor a linear mode. These linear storms will move eastward into a
more moist and unstable airmass, while shear also strengthens and
becomes more southwesterly, likely resulting in a one or more
fast-moving convective lines. Primary hazard within these lines will
be significant wind gusts (75+ mph), although increasing low-level southerly/southeasterly flow with eastern extent could also support
embedded tornadoes. Hail is also possible within the stronger
updrafts, particularly earlier in the convective cycle.

A lower confidence, but still noteworthy, tornado risk will be
associated with any more discrete development that occurs within the
warm sector ahead of any convective lines. Primary forecast
uncertainty results from the inherent limited predictability of the
more mesoscale forcing mechanisms responsible for convective
initiation east of the greater large-scale ascent. Environmental
conditions support supercells capable of all hazards, including
strong tornadoes, with any mature convection. Two areas that appear
to have a relatively higher potential for discrete storms are
east-central into northeast ND, and eastern NE into southeast SD and
western IA/southwest MN. Stronger low-level flow will persist across
these areas, resulting in greater warm-air advection with perhaps
the realization of a discrete storm or two.

...Western and central Kansas and Texas and Oklahoma Panhandles...
Persistent southwesterly flow aloft atop a diurnally destabilizing
airmass is expected to support high-based thunderstorms across
southeast CO/northeast NM this afternoon. These storms are then
expected to persist downstream into the more unstable airmass across
southwest KS, the OK Panhandle, and northern TX Panhandle. Large
hail is possible early in the convective cycle but upscale growth
into a more linear bowing segment is anticipated. Given the high
cloud bases and steep low-level lapse rates, strong to severe gusts
are also possible, including the possibility for a few gusts over 75
mph.

...Middle Mississippi Valley/Lower Ohio Valley...
Airmass destabilization is anticipated this afternoon within the
very moist airmass in place over the region. Thunderstorm
development is expected across the region as a weak MCV, currently
over central MO, tracks southeastward into the region. Shear will be
modest, likely limiting storm organization, but strong buoyancy will
support robust updrafts and the potential for damaging gusts. Given
multiple surface boundaries and the presence of an MCV, a
low-probability tornado risk exists as well.

..Mosier/Squitieri.. 06/09/2026

$$

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ACUS01 KWNS 091955
SWODY1
SPC AC 091953

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 PM CDT Tue Jun 09 2026

Valid 092000Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE
CENTRAL TO NORTHERN HIGH PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
LOWER OHIO VALLEY...

...SUMMARY...
Numerous severe thunderstorms with a potential for 60-80 mph winds
with locally higher gusts, along with tornadoes (some potentially
strong), and large to very large hail are expected across the
northern and central Plains this afternoon and tonight. Severe wind
gusts and large hail will also be possible from north-central and
west-central Kansas southwestward into the Texas Panhandle.

...20z Update...
The previous forecast largely remains on track with only minor
modifications made based on recent trends in observations and model
guidance.

...Kansas/Nebraska...
VWP observations and 18z RAOBs from Grand Junction, CO sampled a
60-70 knot speed maxima embedded within the mid-level flow at about
6 km MSL. Recent mesoanalysis estimates and model guidance appear to
be under-analyzing this feature and show a more diffuse mid-level
jet of around 50 knots. As this stronger flow spreads east into the
Plains it will not only yield stronger deep-layer shear, but will
also promote faster storm motions downstream across the central
Plains. With convective initiation well underway across the High
Plains of NM and CO, confidence is fairly high in the development of
one or more convective bands across KS/NE later this
afternoon/evening. With the expectation for stronger mid-level
flow/deep-layer shear, it appears the potential for severe gusts is
just as high across north-central KS/south-central NE as it is
further north/south and warrants a unification of the 30% wind
probabilities.

...Eastern Dakotas/western Minnesota...
Latest GOES imagery and surface observations show a band of
deepening cumulus within a plume of rich low-level moisture
(dewpoints in the upper 60s to low 70s) through the upper Red River
Valley of the North. Additionally, a subtle MCV - the remnants of
prior convection over NE - is currently overspreading the region and
may provide adequate forcing for ascent for initiation within the
weakly capped and highly buoyant air mass this afternoon. While
conditional, discrete convection that can develop within this zone
could pose a tornado threat as low-level winds strengthen through
the day. The 10% tornado contour was expanded eastward into western
MN to better address this potential.

...Indiana/Ohio...
Latest HRRR/RRFS time-lagged ensemble guidance suggests a
semi-organized convective band may emerge across northern IN into
western OH later this afternoon and into the evening hours ahead of
an MCV (currently noted over central IL). Regional radars show the
early stages of cluster development across central to eastern IL
ahead of the MCV, which lends credibility to this scenario. However,
outflow boundaries are noted ahead of some of this convection,
hinting that the overall intensity of this activity may remain
somewhat modest. Nonetheless, 5% wind probabilities were expanded
downstream to highlight the potential for sporadic damaging winds.

..Moore.. 06/09/2026

.PREV DISCUSSION... /ISSUED 1135 AM CDT Tue Jun 09 2026/

...Central and Northern Plains...
Current satellite imagery shows negatively tilted upper troughing
from the Pacific Northwest into the central Rockies, with an
embedded shortwave trough emerging over the northern/central High
Plains. This shortwave is forecast to continue northeastward today,
with associated height falls spreading from the northern/central
High Plains into the northern/central Plains and Upper Midwest.

Recent surface analysis shows a moist airmass across the Plains,
although notable airmass modification has occurred across KS and
western MO from an overnight MCS. Outflow associated with this MCS
currently arcs from south-central KS through extreme northeast OK
and southwest MO into south-central MO. Convective outflow also
exists over south-central NE. These features add to an already
complex surface pattern which features several lows along a wavy
surface trough from north-central MO into southeast CO. A stationary
boundary also extends northeastward from the low over southeast MT
through south/eastern ND and far northwest MN.

General expectation is for the north/central High Plains to eject
over the northern Plains, with the associated large-scale ascent and convergence along the cold front contributing to thunderstorms
across a large portion of the northern and central Plains. Very
strong buoyancy (i.e. MLCAPE over 2500 J/kg) will be in place across
much of this region, with potential pockets of extreme buoyancy
(i.e. MLCAPE over 4000 J/kg) from eastern SD through eastern
NE/extreme western IA. Thunderstorms are expected to form near the front/dryline by mid/late afternoon, along the western edge of the
greater buoyancy from the west-central Dakotas southward into
western Nebraska. High LCLs and more southerly deep-layer shear will
favor a linear mode. These linear storms will move eastward into a
more moist and unstable airmass, while shear also strengthens and
becomes more southwesterly, likely resulting in a one or more
fast-moving convective lines. Primary hazard within these lines will
be significant wind gusts (75+ mph), although increasing low-level southerly/southeasterly flow with eastern extent could also support
embedded tornadoes. Hail is also possible within the stronger
updrafts, particularly earlier in the convective cycle.

A lower confidence, but still noteworthy, tornado risk will be
associated with any more discrete development that occurs within the
warm sector ahead of any convective lines. Primary forecast
uncertainty results from the inherent limited predictability of the
more mesoscale forcing mechanisms responsible for convective
initiation east of the greater large-scale ascent. Environmental
conditions support supercells capable of all hazards, including
strong tornadoes, with any mature convection. Two areas that appear
to have a relatively higher potential for discrete storms are
east-central into northeast ND, and eastern NE into southeast SD and
western IA/southwest MN. Stronger low-level flow will persist across
these areas, resulting in greater warm-air advection with perhaps
the realization of a discrete storm or two.

...Western and central Kansas and Texas and Oklahoma Panhandles...
Persistent southwesterly flow aloft atop a diurnally destabilizing
airmass is expected to support high-based thunderstorms across
southeast CO/northeast NM this afternoon. These storms are then
expected to persist downstream into the more unstable airmass across
southwest KS, the OK Panhandle, and northern TX Panhandle. Large
hail is possible early in the convective cycle but upscale growth
into a more linear bowing segment is anticipated. Given the high
cloud bases and steep low-level lapse rates, strong to severe gusts
are also possible, including the possibility for a few gusts over 75
mph.

...Middle Mississippi Valley/Lower Ohio Valley...
Airmass destabilization is anticipated this afternoon within the
very moist airmass in place over the region. Thunderstorm
development is expected across the region as a weak MCV, currently
over central MO, tracks southeastward into the region. Shear will be
modest, likely limiting storm organization, but strong buoyancy will
support robust updrafts and the potential for damaging gusts. Given
multiple surface boundaries and the presence of an MCV, a
low-probability tornado risk exists as well.

$$

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ACUS01 KWNS 100105
SWODY1
SPC AC 100104

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0804 PM CDT Tue Jun 09 2026

Valid 100100Z - 101200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL AND NORTHERN PLAINS...

...SUMMARY...
Numerous severe thunderstorms with a potential for 60-80 mph winds
with locally higher gusts, along with tornadoes (some potentially
strong), and large to very large hail are expected across the
northern and central Plains this evening into tonight.

...Central and Northern Plains...
On water vapor imagery, a mid-level shortwave trough appears to be
located from eastern Montana southeastward into western South Dakota
and west-central Nebraska. At the surface, a 996 mb low is currently
located in northwestern North Dakota with a cold front extending
southward from the low. A dryline is evident from central South
Dakota into western Nebraska. To the east of the front and dryline,
a moist airmass is in place with surface dewpoints in the mid to
upper 60s F, which is contributing to moderate to strong
instability. Thunderstorms are currently developing along the entire
length of the front and dryline. Storms that remain discrete or
semi-discrete over the next couple of hours could be supercells,
with a potential to produce tornadoes and large to very large hail.
A couple of strong tornadoes may occur with supercells that are
intense. As convective coverage rapidly increases over the next
couple of hours, a transition to linear mode is expected with a
squall line forming and moving eastward across the remainder of the
Dakotas this evening.

Along and near the instability axis, the RAP has 0-3 km lapse rates
in the 8 to 8.5 C/km range. In addition, 0-6 km shear near this axis
is around 45 knots, as is evident on the Bismarck and Aberdeen
WSR-88D VWPs. This environment will be very favorable for severe
wind gusts, and some gusts could exceed 80 mph along the more
intense parts of the line. While a tornado threat will exist with
supercells early on, a continued tornado threat is expected as the
squall line develops with embedded rotating cells. The potential for
severe wind gusts and tornadoes will continue into the late evening
and overnight period as the line moves eastward into the upper
Mississippi Valley.

Further south into the central Plains, the RAP has a pocket of
strong instability analyzed over east-central Nebraska, where the
RAP shows MLCAPE in the 4500 to 5500 J/kg range. Severe
thunderstorms have developed to the west and south of this
instability maximum. The RAP also has a 40 to 50 knot low-level jet
max in far northern Kansas. As this feature strengthens and moves
northeastward into eastern Nebraska, low-level shear will become
increasingly favorable for tornadoes. Supercells that can become
robust may be able to produce a strong tornado or two.

Southward into central Kansas, strong instability is analyzed by the
RAP over much of central and northeastern Kansas, where MLCAPE is
estimated to be from 3000 to 4500 J/kg. In addition, moderate
deep-layer shear is present and low to mid-level lapse rates are
steep. This will support a threat for large hail and severe wind
gusts this evening with the stronger supercells and short line
segments.

...Ohio Valley...
A moist and unstable airmass is currently located across much of the
Ohio Valley. An axis of instability is analyzed from southern
Illinois east-northeastward across southern Indiana and northwest
Ohio. Scattered thunderstorms are ongoing in west-central Indiana
just to the west of the instability axis. Ahead of the storms,
low-level lapse rates are steep. This will contribute to a potential
for isolated severe gusts over the next hour or two.

..Broyles.. 06/10/2026

$$

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ACUS01 KWNS 100601
SWODY1
SPC AC 100559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Wed Jun 10 2026

Valid 101200Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER MISSISSIPPI VALLEY AND MIDWEST...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail in excess of two inches in diameter, a few strong tornadoes and
damaging winds with gusts over 75 mph are expected this afternoon
and evening across parts of the Upper Mississippi Valley and
Midwest.

...Upper Mississippi Valley/Midwest...
At mid-levels, a trough will move eastward into the central and
northern Plains today, as the exit region of a jet streak
overspreads the upper Mississippi Valley and Midwest. At the
surface, a cold front will advance eastward across the northern
Plains with a warm front moving into the western Great Lakes.
Between these two fronts, a very moist airmass will be in place with
surface dewpoints in the lower to mid 70s F. Early in the day, a
line of strong thunderstorms is expected to develop in western Iowa
near the western edge of the moist airmass. A potential for severe
wind gusts will be possible with this line. Eastward across the
moist sector, moderate to strong instability is expected to develop
by midday as surface temperatures warm. This will help the line to
grow upscale, potentially into a linear MCS, as it moves across
southern Wisconsin and northern Illinois early this afternoon.
Severe wind gusts and QLCS tornadoes will be possible along the
stronger parts of this line segment.

In the wake of the initial line segment, instability is expected to
increase as moisture advection and surface heating take place. An
instability axis is forecast to develop in the afternoon from
eastern Missouri northward into eastern Iowa, where MLCAPE should
increase into the 3000 to 3500 J/kg range. Thunderstorm development
will be likely during the mid to late afternoon along a zone of
low-level convergence from northern Missouri into central and
eastern Iowa. Additional storms are expected to form further north
into parts of far eastern Minnesota and western Wisconsin. RAP
forecast soundings in the late afternoon from eastern Iowa into
southwest Wisconsin have curved hodographs, with 0-6 km shear near
40 knots, and 0-3 km storm-relative helicity around 225 m2/s2. This
environment will support supercells with tornado potential. A strong
tornado or two will be possible as supercells move eastward in a
strengthening low-level jet during the late afternoon and early
evening. Large hail and wind damage will also be possible with
supercells. From this cluster, a second severe line segment with
damaging wind gusts is expected to develop. This line will likely
impact parts of northeast Missouri and north-central Illinois.

Further southwest across parts of northwest/north-central Missouri
and northeast Kansas, scattered thunderstorm development is expected
during the late afternoon and early evening. These storms will be
located near an axis of strong instability, along which RAP
forecasts suggest that 0-6 km shear will be in around 40 knots. In
addition 700-500 mb lapse rates are forecast to be near 7.5 C/km.
The environment should support large hail and severe wind gusts.

...Ohio Valley/Central Appalachians...
A moist and unstable airmass will be in place today across much of
the region, with surface dewpoints in the lower to mid 70s F.
Although large-scale ascent will be weak, isolated thunderstorms
appear likely to develop in areas where low-level convergence
becomes maximized. Forecast soundings across the Ohio Valley show
steep low-level lapse rates during the afternoon and have enough
deep-layer shear for a localized severe threat. A few of the
stronger cells could produce isolated severe gust and hail.

..Broyles/Lyons.. 06/10/2026

$$

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ACUS01 KWNS 101255
SWODY1
SPC AC 101254

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 AM CDT Wed Jun 10 2026

Valid 101300Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER MISSISSIPPI VALLEY AND MIDWEST...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail in excess of two inches in diameter, a few strong tornadoes and
damaging winds with gusts over 75 mph are expected this afternoon
and evening across parts of the Upper Mississippi Valley and
Midwest.

...Midwest/Missouri Valley and Upper Mississippi Valley...
With a broad upper trough centered near/east of the northern CONUS
and Canadian Rockies, its lead portion will shift northeastward over
the Upper Midwest/Lake Superior vicinity today, with more limited
forcing for ascent and height falls farther south, until the
late-night arrival of a secondary portion of this trough out of the
northern Rockies and north-central High Plains. The primary synoptic low/surface triple point will shift from northern Minnesota
north-northeastward into Canada. A moist environment will be in
place to the east of an eastward-advancing cold front, with
north-northeastward air mass recovery in the wake of overnight/early
morning storms (MCS) across the eastern Dakotas and
Minnesota/Wisconsin.

Showers and thunderstorms have increased in the predawn hours across
eastern portions of Nebraska/Kansas into northwest Missouri and
western Iowa. This development is driven by a strong southwesterly
low-level jet and ample elevated moisture transport. For additional
short-term details, see Mesoscale Discussion 1063. This development
could further increase today and shift east-northeastward across
Iowa/northern Missouri and eventually northwest Illinois today,
complexifying the forecast scenario. These storms could pose a
severe-storm risk within this corridor relatively early today, with
subsequent development expected by late afternoon near the cold
front spanning Minnesota into east-central Iowa, northern Missouri
and eastern Kansas. The early day storms, pending how extensive they
are, could spatially influence via outflow/cloud debris a preferred
zone for redevelopment near the Iowa/Missouri border vicinity toward west-central/northwest Illinois. Meanwhile, farther north, in closer
proximity to the large-scale height falls, another preferred zone of severe-storm development could focus across northern/eastern
Minnesota into western Wisconsin.

Deep-layer shear will be strengthening across these regions and will
broadly support initial supercells capable of large hail, with very
large hailstones possible with initial development near the cold
front late this afternoon and early evening. A predominant large
hail risk is also expected late tonight with anticipated mostly
elevated development across central/eastern Nebraska and northeast
Kansas, attributable to the approaching upstream system and an
re-intensifying low-level jet and warm/moist advection. Large hail
aside, tornadoes will be possible regionally late this afternoon and
evening, a few of which could be strong (EF2+). The early day storms
could ultimately organize and pose a damaging wind threat, and more
broadly so this evening as storms trend upscale near/east of the
cold front, potentially leading to a multi-round severe potential in
some areas today and tonight.

...Ohio Valley/Central Appalachians/Mid-Atlantic States...
A moist and unstable airmass will be in place today across much of
the region, with surface dewpoints generally in the lower 70s F.
While some thunderstorms are ongoing early today, additional and
more potent thunderstorm development is expected into the afternoon
as the boundary layer destabilizes. This development will be further
influenced by one or more weak eastward-moving MCVs over the upper
Ohio River Valley this morning. Damaging winds will be the primary
hazard regionally.

..Guyer/Wendt.. 06/10/2026

$$

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ACUS01 KWNS 101634
SWODY1
SPC AC 101632

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1132 AM CDT Wed Jun 10 2026

Valid 101300Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER/MID MISSISSIPPI VALLEYS AND MIDWEST...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail in excess of two inches in diameter, a few strong tornadoes and
damaging winds with gusts over 75 mph are expected this afternoon
and evening across parts of the Upper Mississippi Valley and
Midwest.

...Mid/Upper MS Valley into the central Plains...
Regional radar imagery shows an ongoing cluster of strong
thunderstorms across southern IA and northern MO, supported by a
residual low-level jet that currently extends from KS/northern OK
into the region. Heating of the very moist airmass downstream will
result in limited convective inhibition and strong to very strong
buoyancy by the early afternoon. Reintensification of the ongoing
cluster is anticipated as it moves within this destabilizing
airmass. Deep-layer shear will be modest but still sufficient for
some organization, and the development of a strong to occasionally
severe bowing line segment appears probable, particularly from
northeast IA into southern WI and northern IL. New updrafts ahead of
the line could also produce hail early in the convective cycle,
while also potentially contributing to updraft augmentation as they
merge into the line. Some isolated hail could result from this
augmentation as well.

Farther north, recent surface analysis placed a triple point low
over northeast SD. An occluded front extends north-northwestward
from this low across eastern ND into central Manitoba, while cold
front extends southward to another low over northeast NE and then
back southwestward across the central Plains. The frontal zone and
triple point low are forecast to progress eastward into the Upper
Midwest, interacting with a diurnally destabilizing airmass to
support thunderstorm development. Ample low-level moisture (i.e.
dewpoints in the upper 60s/low 70s) will support strong buoyancy,
despite modest lapse rates, and moderate deep-layer vertical shear
should be sufficient for updraft organization. As a result, strong
to severe thunderstorms are expected along and just ahead the front,
with large hail as the primary threat. Isolated very large hail to
2" in diameter could occur. Some damaging gusts are possible as
storms transition into bowing line segments over time. There is also
a low-probability for a few brief tornadoes, particularly with any
more cellular development from central into eastern WI from 21 to
00Z.

An additional severe threat will likely materialize this evening in
the wake of the afternoon MCS within the recovered airmass from the
Mid MS Valley westward through the Mid MO Valley into the central
Plains. The impetus for this redevelopment will likely be a complex
combination of low-level convergence along the approaching front,
low-level convergence and warm-air advection along remnant outflow,
and modest large-scale ascent. Development along the front appears
most likely from central IA southwestward into northeast KS, while
development along the outflow appears most likely northwest IL
across southern IA. The airmass in all of these areas will likely
feature ample low-level moisture (i.e. dewpoints in the low to mid
70s), warm surface temperatures (highs in the low 90s), and at least
modestly steep mid-level lapse rates. This will result in strong to
extreme buoyancy, with MLCAPE values exceeding 3000 J/kg from
northeast KS into southern IA, northern MO, and west-central IL.

Complex surface pattern will likely yield limited predictability for
the primary severe hazard this evening. Given the extreme buoyancy
and moderate mid-level flow, any more cellular development that is
able to mature should become supercellular, with all severe hazards
possible, including very large hail and tornadoes. Storm interaction
and strong downdrafts will likely make maintaining a discrete mode
difficult, but low-level hodographs support the potential for a
strong tornado, particularly from 00 to 03Z amid a strengthening
low-level jet.

Lastly, early morning strong to severe thunderstorms are possible
across central/eastern NE as a secondary branch of the low-level jet
develops in response to another shortwave trough moving into the
central High Plains.

...Ohio Valley/Central Appalachians/Mid-Atlantic States...
A moist and unstable airmass will be in place today across much of
the region, with surface dewpoints generally in the lower 70s F.
While some thunderstorms are ongoing early today, additional and
more potent thunderstorm development is expected into the afternoon
as the boundary layer destabilizes. These storms will be further
influenced by a pair of weak eastward-moving MCVs, one over the
upper Ohio River Valley and the other over the central Appalachians.
Damaging winds, associated with water-loaded downbursts, will be the
primary hazard regionally.

..Mosier/Flournoy.. 06/10/2026

$$

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ACUS01 KWNS 101708
SWODY1
SPC AC 101706

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1206 PM CDT Wed Jun 10 2026

Valid 101630Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER/MID MISSISSIPPI VALLEYS AND MIDWEST...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail in excess of two inches in diameter, a few strong tornadoes and
damaging winds with gusts over 75 mph are expected this afternoon
and evening across parts of the Upper Mississippi Valley and
Midwest.

...Mid/Upper MS Valley into the central Plains...
Regional radar imagery shows an ongoing cluster of strong
thunderstorms across southern IA and northern MO, supported by a
residual low-level jet that currently extends from KS/northern OK
into the region. Heating of the very moist airmass downstream will
result in limited convective inhibition and strong to very strong
buoyancy by the early afternoon. Reintensification of the ongoing
cluster is anticipated as it moves within this destabilizing
airmass. Deep-layer shear will be modest but still sufficient for
some organization, and the development of a strong to occasionally
severe bowing line segment appears probable, particularly from
northeast IA into southern WI and northern IL. New updrafts ahead of
the line could also produce hail early in the convective cycle,
while also potentially contributing to updraft augmentation as they
merge into the line. Some isolated hail could result from this
augmentation as well.

Farther north, recent surface analysis placed a triple point low
over northeast SD. An occluded front extends north-northwestward
from this low across eastern ND into central Manitoba, while cold
front extends southward to another low over northeast NE and then
back southwestward across the central Plains. The frontal zone and
triple point low are forecast to progress eastward into the Upper
Midwest, interacting with a diurnally destabilizing airmass to
support thunderstorm development. Ample low-level moisture (i.e.
dewpoints in the upper 60s/low 70s) will support strong buoyancy,
despite modest lapse rates, and moderate deep-layer vertical shear
should be sufficient for updraft organization. As a result, strong
to severe thunderstorms are expected along and just ahead the front,
with large hail as the primary threat. Isolated very large hail to
2" in diameter could occur. Some damaging gusts are possible as
storms transition into bowing line segments over time. There is also
a low-probability for a few brief tornadoes, particularly with any
more cellular development from central into eastern WI from 21 to
00Z.

An additional severe threat will likely materialize this evening in
the wake of the afternoon MCS within the recovered airmass from the
Mid MS Valley westward through the Mid MO Valley into the central
Plains. The impetus for this redevelopment will likely be a complex
combination of low-level convergence along the approaching front,
low-level convergence and warm-air advection along remnant outflow,
and modest large-scale ascent. Development along the front appears
most likely from central IA southwestward into northeast KS, while
development along the outflow appears most likely northwest IL
across southern IA. The airmass in all of these areas will likely
feature ample low-level moisture (i.e. dewpoints in the low to mid
70s), warm surface temperatures (highs in the low 90s), and at least
modestly steep mid-level lapse rates. This will result in strong to
extreme buoyancy, with MLCAPE values exceeding 3000 J/kg from
northeast KS into southern IA, northern MO, and west-central IL.

Complex surface pattern will likely yield limited predictability for
the primary severe hazard this evening. Given the extreme buoyancy
and moderate mid-level flow, any more cellular development that is
able to mature should become supercellular, with all severe hazards
possible, including very large hail and tornadoes. Storm interaction
and strong downdrafts will likely make maintaining a discrete mode
difficult, but low-level hodographs support the potential for a
strong tornado, particularly from 00 to 03Z amid a strengthening
low-level jet.

Lastly, early morning strong to severe thunderstorms are possible
across central/eastern NE as a secondary branch of the low-level jet
develops in response to another shortwave trough moving into the
central High Plains.

...Ohio Valley/Central Appalachians/Mid-Atlantic States...
A moist and unstable airmass will be in place today across much of
the region, with surface dewpoints generally in the lower 70s F.
While some thunderstorms are ongoing early today, additional and
more potent thunderstorm development is expected into the afternoon
as the boundary layer destabilizes. These storms will be further
influenced by a pair of weak eastward-moving MCVs, one over the
upper Ohio River Valley and the other over the central Appalachians.
Damaging winds, associated with water-loaded downbursts, will be the
primary hazard regionally.

..Mosier/Flournoy.. 06/10/2026

$$

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ACUS01 KWNS 102001
SWODY1
SPC AC 101959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Wed Jun 10 2026

Valid 102000Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE
UPPER MISSISSIPPI VALLEY INTO PARTS OF THE PLAINS...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail in excess of two inches in diameter, a few strong tornadoes and
damaging winds with gusts over 75 mph are expected this afternoon
and evening across parts of the Upper Mississippi Valley and
Midwest.

...20z Update...
Only minor adjustments were made to the ongoing forecast based on
recent convective trends and recent high-res guidance.

...Upper MS Valley/Great Lakes...
As of 20 UTC, regional radar mosaics depict a mature MCS ongoing
across northern IL into northern WI with multiple severe gusts
reported over the past few hours (see MCD #1066 for additional
short-term details). Behind the MCS, a stout cold pool is in place
from northeast MO into eastern IA and southeast MN featuring
temperatures in the low 70s under a cirrus canopy. This cold pool
casts some uncertainty on the degree of air mass recovery, and
recent high-res guidance suggests that the primary severe threat may
have passed for portions of the region. 30% wind probabilities were
reduced to reflect this trend; however, southwesterly flow from the
surface through 500 mb is advecting higher theta-e air in the low
levels and steeper mid-level lapse rates east/northeastward into the
cold pool. This will support re-development of strong to severe
thunderstorms later this evening with primarily a risk for very
large hail, so maintained Enhanced-caliber hail probabilities to
reflect this potential.

...Central Kansas/northwest Missouri...
A volatile environment is emerging from central KS to northwest MO
where MLCAPE is increasing to 3000-3500 J/kg per an 18 UTC TOP RAOB
and recent mesoanalysis estimates. Additionally, the 18 UTC RAOB
sampled effective bulk shear on the order of 50 knots as well as
strong veering through the lowest kilometer. This environment is
highly favorable for intense supercells, which appear likely in the
coming hours based on recent GOES visible imagery (see MCD #1067 for
additional short-term details). Recent HRRR/RRFS time-lagged
ensemble guidance and WoFS solutions all suggest the highest hail
and tornado threat will likely emerge from the Salina, KS area
northeastward into northwest MO through the evening. Storm mode
remains a modulating factor with upscale growth likely, but a window
exists for very strong discrete/semi-discrete supercells. Both
tornado and hail risk contours were adjusted west/southwestward to
reflect these recent trends.

...Eastern Nebraska/far western Iowa...
Latest forecast guidance continues to show a signal for elevated
convection near the terminus of a low-level jet across eastern
NE/western IA late tonight/early Thursday morning. Forecast
soundings from these solutions, most notably recent RAP runs and the
12z NAM, hint that low-level moisture advection may be sufficient to
support parcels rooted near the surface. While the potential is
fairly low, there is some potential for a tornado threat if
low-level moistening is sufficient given an otherwise favorable
near-surface wind profile, warranting the introduction of 2% tornado probabilities.

..Moore.. 06/10/2026

.PREV DISCUSSION... /ISSUED 1256 PM CDT Wed Jun 10 2026/

...Mid/Upper MS Valley into the central Plains...
Regional radar imagery shows an ongoing cluster of strong
thunderstorms across southern IA and northern MO, supported by a
residual low-level jet that currently extends from KS/northern OK
into the region. Heating of the very moist airmass downstream will
result in limited convective inhibition and strong to very strong
buoyancy by the early afternoon. Reintensification of the ongoing
cluster is anticipated as it moves within this destabilizing
airmass. Deep-layer shear will be modest but still sufficient for
some organization, and the development of a strong to occasionally
severe bowing line segment appears probable, particularly from
northeast IA into southern WI and northern IL. New updrafts ahead of
the line could also produce hail early in the convective cycle,
while also potentially contributing to updraft augmentation as they
merge into the line. Some isolated hail could result from this
augmentation as well.

Farther north, recent surface analysis placed a triple point low
over northeast SD. An occluded front extends north-northwestward
from this low across eastern ND into central Manitoba, while cold
front extends southward to another low over northeast NE and then
back southwestward across the central Plains. The frontal zone and
triple point low are forecast to progress eastward into the Upper
Midwest, interacting with a diurnally destabilizing airmass to
support thunderstorm development. Ample low-level moisture (i.e.
dewpoints in the upper 60s/low 70s) will support strong buoyancy,
despite modest lapse rates, and moderate deep-layer vertical shear
should be sufficient for updraft organization. As a result, strong
to severe thunderstorms are expected along and just ahead the front,
with large hail as the primary threat. Isolated very large hail to
2" in diameter could occur. Some damaging gusts are possible as
storms transition into bowing line segments over time. There is also
a low-probability for a few brief tornadoes, particularly with any
more cellular development from central into eastern WI from 21 to
00Z.

An additional severe threat will likely materialize this evening in
the wake of the afternoon MCS within the recovered airmass from the
Mid MS Valley westward through the Mid MO Valley into the central
Plains. The impetus for this redevelopment will likely be a complex
combination of low-level convergence along the approaching front,
low-level convergence and warm-air advection along remnant outflow,
and modest large-scale ascent. Development along the front appears
most likely from central IA southwestward into northeast KS, while
development along the outflow appears most likely northwest IL
across southern IA. The airmass in all of these areas will likely
feature ample low-level moisture (i.e. dewpoints in the low to mid
70s), warm surface temperatures (highs in the low 90s), and at least
modestly steep mid-level lapse rates. This will result in strong to
extreme buoyancy, with MLCAPE values exceeding 3000 J/kg from
northeast KS into southern IA, northern MO, and west-central IL.

Complex surface pattern will likely yield limited predictability for
the primary severe hazard this evening. Given the extreme buoyancy
and moderate mid-level flow, any more cellular development that is
able to mature should become supercellular, with all severe hazards
possible, including very large hail and tornadoes. Storm interaction
and strong downdrafts will likely make maintaining a discrete mode
difficult, but low-level hodographs support the potential for a
strong tornado, particularly from 00 to 03Z amid a strengthening
low-level jet.

Lastly, early morning strong to severe thunderstorms are possible
across central/eastern NE as a secondary branch of the low-level jet
develops in response to another shortwave trough moving into the
central High Plains.

...Ohio Valley/Central Appalachians/Mid-Atlantic States...
A moist and unstable airmass will be in place today across much of
the region, with surface dewpoints generally in the lower 70s F.
While some thunderstorms are ongoing early today, additional and
more potent thunderstorm development is expected into the afternoon
as the boundary layer destabilizes. These storms will be further
influenced by a pair of weak eastward-moving MCVs, one over the
upper Ohio River Valley and the other over the central Appalachians.
Damaging winds, associated with water-loaded downbursts, will be the
primary hazard regionally.

$$

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ACUS01 KWNS 110121
SWODY1
SPC AC 110119

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0819 PM CDT Wed Jun 10 2026

Valid 110100Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE UPPER MISSISSIPPI VALLEY INTO PARTS OF THE PLAINS...

...SUMMARY...
Scattered to numerous severe thunderstorms with potential for large
hail, a couple of tornadoes and damaging winds with gusts over 75
mph will continue this evening across parts of the Upper Mississippi
Valley and Midwest.

...Synopsis...
A cold front extends from portions of the upper Midwest into the
central Plains, with a surface low over Manitoba. Several lines and
clusters of severe thunderstorms continue along and ahead of this
feature across portions of the Great Lakes into the Midwest and central/southern Plains. The risk for damaging wind, large hail, and
a couple of tornadoes will continue into the evening across these
regions extending into the Ohio Valley overnight.

...Central Kansas, northwest Missouri and Iowa...
Widespread thunderstorm development continues across central Kansas
into central Iowa along the cold front. Initial development is
supercelluar and pose a risk for large hail, damaging wind, and
perhaps a tornado. Linear forcing along the front will likely lead
to upscale growth, with the primary threat becoming damaging wind.
Ongoing convection further west into southern Iowa/northwest
Missouri is remaining a mixed-mode of supercells and multi-cell
clusters. Within this area, strong instability and deep layer shear
may continue to pose a risk for a tornado or two while storm mode
remains semi-discrete. The 10% tornado risk and 30% hail risk areas
were removed with this update given the tendency for more linear
storm modes.

...Eastern Nebraska/far western Iowa and northern Illinois...
Latest forecast guidance continues to show a signal for elevated
convection near the terminus of a low-level jet across eastern
NE/western IA late tonight/early Thursday morning. Forecast
soundings from these solutions, most notably recent RAP runs and the
NAM, hint that low-level moisture advection may be sufficient to
support parcels rooted near the surface. Initial thunderstorms may
pose a risk for hail before growing upscale into a damaging MCS into
the end of the current D1 period tomorrow morning. A 30% wind area
was introduced into southeastern Nebraska/southern Iowa in support
of recent HRRR runs which show potential for a swath of damaging
wind across far eastern Nebraska into southern Iowa.

..Thornton.. 06/11/2026

$$

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ACUS01 KWNS 110621
SWODY1
SPC AC 110619

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0119 AM CDT Thu Jun 11 2026

Valid 111200Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THURSDAY INTO
THURSDAY NIGHT ACROSS PARTS OF SOUTHERN AMD EASTERN IOWA
...NORTHEASTERN MISSOURI...NORTHERN AND CENTRAL ILLINOIS...SOUTHERN WISCONSIN...NORTHERN INDIANA AND CENTRAL AND SOUTHERN LOWER
MICHIGAN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THURSDAY AFTERNOON
ACROSS THE ALLEGHENY MOUNTAINS THROUGH NORTHERN MID ATLANTIC
VICINITY...

...SUMMARY...
Strong to severe thunderstorm development, including one or two
organizing clusters, will probably be accompanied by the potential
for large hail, damaging wind gusts and perhaps a couple of strong
tornadoes in a corridor across the Midwest into Great Lakes region
Thursday through Thursday night.

...Synopsis...
A potent mid-level trough will eject across the Upper Midwest into
the Great Lakes region today, with unseasonably strong 80-100 kt
southwesterly mid-level flow over spreading portions of the
upper-Midwest. An attendant surface low will deepen lift northward
out of the central Plains into the Midwest and Great Lakes, with a
trailing cold front extending into the central/southern Plains and
warm front/modifying outflow lifting northward into the upper
Midwest/Great Lakes. Elsewhere, northwest flow is expected in the
mid levels across the Mid-Atlantic, with a series of weaker
disturbances moving through that region.

A severe MCS is expected to be ongoing at the start of the D1 period
across portions of southern Iowa into western Illinois, posing a
risk for strong to potential significant wind gusts. Additional
development is expected behind the morning MCS along the cold front
and in the vicinity of remnant outflow from the morning MCS.
Supercells capable of large to very large hail, damaging wind, and
tornadoes (a few strong) will be possible before upscale growth and
eventual evolution to a damaging wind threat into the evening.

...Mid/lower Missouri Valley into the Mid Mississippi Valley and
upper Great Lakes...
The low-level jet is expected to strengthen this morning across the
central Plains, with convection developing across southeastern
Nebraska early this morning. This initial development will likely be supercellular and initially elevated, given strong deep layer shear
and returning moisture. Large hail will be the main concern before
cells cluster and beginning to organize along outflow. Hi-res
guidance trends have been for an organized MCS to develop and spread
eastward into portions of southern/central Iowa and northern
Illinois. Given the strengthening upper level flow and increasing
moisture, this will become surface based with the potential to
produce strong to significant wind gusts (some 70-75+ mph) in the
morning to mid-afternoon possibly extending into portions of
Michigan.

Much of the afternoon severe potential remains contingent on how the
morning MCS evolves. It is likely that a modifying outflow/warm
front will lift northward and settle into northern Illinois/southern
Wisconsin by the afternoon with the cold front further west. The
continued strong low-level jet should support strong warm air
advection and quick air mass recovery into northern
Illinois/southern Wisconsin. Additional thunderstorms are expected
to develop along the front and near the modifying boundary. Strongly
sheared profiles will support initial supercells capable of large
hail and tornadoes (a few of which may be strong to intense). There
remains some uncertainty in where the placement of the boundary will
be and how long discrete supercell storm modes can be maintained. It
is possible that a corridor of higher tornado potential will become
clear with need to include higher probabilities as details become
clearer in further outlook updates.

Eventual upscale growth is anticipated as the frontal forcing shifts
eastward. Bowing segments capable of strong to significant gusts
will likely emerge. Wind probabilities were increased (with addition
of a 45% area) with this outlook to account for the morning MCS and
for potential for a secondary round of severe to significant wind
gusts. It is possible that higher probabilities may be needed with
further outlook updates.

...Eastern Kansas into the Southern Plains...
Additional thunderstorm development is expected along the trailing
cold front into portions of the central/southern Plains. Deep layer
shear will remain mostly post-frontal, however, around 20-30 kts
effective bulk shear and moderate to strong instability will support
some supercell structures capable of large hail and damaging wind.
Storm motions and boundary parallel shear will likely lead to
clustering and messy modes through time.

...Mid-Atlantic into central Appalachians...
Forcing for ascent from multiple short-wave disturbances across the
northeast and dew points in the 60s to 70s will support development
of widely scattered thunderstorm activity by the afternoon across
the Mid-Atlantic into the central Appalachians. Though shear will be
generally weak, moderate to strong instability will be in place will
support stronger updrafts capable of damaging wind. It is likely
that several clusters will emerge with potential for organizing
along cold pools and more focused corridors of damaging wind
potential. A 30% area was added with this outlook to cover this
potential.

..Thornton/Lyons.. 06/11/2026

$$

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ACUS01 KWNS 111300
SWODY1
SPC AC 111258

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0758 AM CDT Thu Jun 11 2026

Valid 111300Z - 121200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
IOWA AND NORTHERN ILLINOIS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST/MID-ATLANTIC STATES...

...SUMMARY...
Widespread severe thunderstorms are expected across parts of the
Midwest and Great Lakes region, including Iowa, northern Missouri,
northern Illinois and southern Wisconsin to Lower Michigan and
northern Indiana. This includes the potential for widespread/intense
damaging winds, large hail, and tornadoes, some of which may be
strong.

...Midwest/Great Lakes...
Portions of the region have been upgraded to a Moderate Risk.
Another very active day with widespread/intense severe storms is
expected regionally. A consequential severe risk is already ongoing
this morning across Iowa/far northern Missouri, and will continue east-northeastward and become more prominent regionally during the
day. A well-organized/eastward-accelerating bowing cluster of
storms, now supported by an apparent MCV, has had a history of
measured severe-caliber wind gusts overnight and in the predawn
hours from southeast Nebraska into southern Iowa. A similar severe
risk should continue east-northeastward through midday across
eastern Iowa/far northeast Missouri toward northern Illinois, with
more of a surface-based/tornado risk potentially unfolding
relatively early today aside from a continued prominent damaging
wind threat.

Scenario is supported by a robust southwesterly low-level
jet/moisture transport, even with some diurnal weakening of the
low-level jet possible. Also influential is a prominent/increasingly neutral-tilt-shortwave trough and jet streak crossing the Corn Belt,
notably strong features by mid-June standards.

Convective overturning/outflow from last evening's MCS are still
residual factors evident this morning in observational
data/supplemental 3D mesoanalysis across far eastern Iowa, far
northeast Missouri into central Illinois. This is sampled by the 12z
observed sounding from KILX/Lincoln, IL. These residual factors may
somewhat southward-focus the peak/most-intense severe weather later
today, with more uncertainty progressively northward in general
proximity to Lake Michigan latitudinally, including parts of Wisconsin/Michigan. The timing/residual impacts of this morning's
MCS across Iowa/northern Missouri into northern Illinois and severe
potential in its wake near the surface low and front, and/or to its
(MCS) north-northeast are a bit less uncertain. That said, mass
response/fluxes related to the dynamic shortwave trough/speed max
will be notable and consistent with heightened severe-potential even
if outflow/cloud debris exists and sub-regional areas of
destabilization are sub-optimal.

Details of later-afternoon severe potential is somewhat contingent
on how the morning MCS further evolves, but a window for
redevelopment in its immediate wake will probably exist. This will
lead to a renewed round of severe storms as development occurs near
the cold front, and perhaps preferentially favors prior outflow,
with a damaging wind and tornado risk continuing eastward this
evening as the low-level jet re=intensifies and as storms gradually
grow upscale toward Lake Michigan and across Illinois/Indiana/Lower
Michigan.

...Eastern Kansas and Southern Plains...
Additional thunderstorm development is expected along the trailing
cold front into portions of the central/southern Plains. Deep layer
shear will be maximized in the post-frontal environment; however,
around 20-30 kt of effective bulk shear and moderate to strong
instability will support some supercell structures capable of large
hail and damaging winds. Storm motions and boundary parallel shear
will likely lead to clustering and messy modes over time.

...Mid-Atlantic ad central Appalachians...
Forcing for ascent from multiple shortwave disturbances across the
northeast and dewpoints in the 60s to 70s F will support development
of widely scattered thunderstorms by afternoon across the
Mid-Atlantic into the central Appalachians. Though vertical shear
will be generally weak, moderate to strong instability will be in
place will support stronger updrafts capable of damaging winds. It
is likely that several clusters will emerge with potential for
organizing along cold pools and more focused corridors of damaging
wind potential.

..Guyer/Wendt.. 06/11/2026

$$

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ACUS01 KWNS 111624
SWODY1
SPC AC 111622

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1122 AM CDT Thu Jun 11 2026

Valid 111630Z - 121200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
NORTHERN ILLINOIS...FAR EASTERN IOWA...AND FAR SOUTHERN WISCONSIN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC AND CENTRAL APPALACHIANS...

...SUMMARY...
Widespread severe thunderstorms are expected this afternoon and
evening across parts of the Midwest and Great Lakes region,
including far eastern Iowa, northern Missouri, northern/central
Illinois, southern Wisconsin, Lower Michigan, and northern Indiana.
This includes the potential for widespread/intense damaging winds
(some 75+ mph), large hail, and several tornadoes, some of which may
be strong to intense.

...Midwest/Great Lakes...
An active and impactful severe weather event is still expected
across parts of the Midwest Great Lakes later this afternoon and
evening. Ongoing bowing cluster across southeast IA/northwest
IL/southwest WI and vicinity may continue to pose at least some
severe wind and embedded QLCS tornado threat as it continues
east-northeastward across parts of the Midwest this afternoon. There
is still airmass recovery underway ahead of this activity,
especially into central/northern IL, northern IN, and parts of
southern Lower MI where strong heating is occurring. Enhanced
mid-level west-southwesterly winds associated with a potent
shortwave trough over the northern Plains/Upper Midwest will
overspread the developing warm sector this afternoon, and support
organized severe potential, including the possibility of multiple
tornadic supercells and widespread severe/damaging winds.

Even so, greater than usual uncertainty exists regarding
redevelopment later today on the southern/western flank of ongoing
convection across northern IL into northeast MO and vicinity. A
gradual increase in both low-level and deep-layer shear is
anticipated across this area as a 30-40+ kt southerly low-level jet
develops eastward in tandem with the eastward-ejecting shortwave
trough and mid-level jet. A mix of supercells and bowing segments
appears probable as renewed thunderstorms develop along/ahead of the
surface cold front this afternoon in a strongly unstable and rather
favorably sheared environment. If at least semi-discrete supercell
structures can be maintained, then potential exists for several
tornadoes, and multiple strong to intense tornadoes (EF-2/3+) given
the enhanced low-level shear. Isolated large to very large hail may
also occur with any sustained supercells.

Otherwise, numerous to potentially widespread severe/damaging winds
also appear likely through the period across parts of
northern/central IL into southern Lower MI and northern IN. Both the
ongoing cluster and eventual upscale growth of convection that
develops this afternoon will likely produce severe/damaging winds,
some of which could be significant (75+ mph). The northern extent of
the severe risk into WI and northern Lower MI remains uncertain, but
at least some wind and/or tornado threat will likely continue with
eastward extent into the southern Great Lakes and northern IN this
evening.

...Eastern Kansas/Southern Missouri into the Southern Plains...
Additional thunderstorms will likely develop this afternoon and
evening along the trailing cold front into portions of eastern
KS/southern MO into the southern Plains. Stronger deep-layer shear
is forecast to lag behind/to the north of the cold front. Still,
around 20-30 kt of effective bulk shear and moderate to strong
instability will support marginal supercell structures and loosely
organized multicells capable of producing both large hail and
damaging winds. A large component of boundary-parallel shear will
likely lead to clustering and messy convective modes through the
evening before thunderstorms gradually weaken with the loss of
daytime heating.

...Mid-Atlantic/Central Appalachians...
Recent visible satellite imagery across much of the Mid-Atlantic and
central Appalachians shows mostly sunny to partly cloudy conditions,
with ample low-level moisture present per latest surface
observations and area 12Z observed soundings. Large-scale ascent
associated with multiple low-amplitude mid-level shortwave troughs
will likely support the development of widely scattered
thunderstorms by afternoon across parts of the Mid-Atlantic into the
central Appalachians. Though deep-layer shear is forecast to remain
modest, moderate to strong instability will exist with continued
diurnal heating this afternoon. This will support stronger updrafts
capable of scattered severe/damaging winds and perhaps isolated
hail. Multiple clusters should eventually emerge, with potential for
organizing along outflow/cold pools, and more focused corridors of
damaging winds possible across parts of the I-95 corridor from
northern VA to eastern PA and NJ.

..Gleason/Flournoy.. 06/11/2026

$$

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ACUS01 KWNS 111954
SWODY1
SPC AC 111953

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 PM CDT Thu Jun 11 2026

Valid 112000Z - 121200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER
OHIO VALLEY AND MID-ATLANTIC REGIONS...

...SUMMARY...
Widespread severe thunderstorms are expected this afternoon and
evening across parts of the Midwest and Great Lakes region,
including far eastern Iowa, northern Missouri, northern/central
Illinois, southern Wisconsin, Lower Michigan, and northern Indiana.
This includes the potential for widespread/intense damaging winds
(some 75+ mph), large hail, and several tornadoes, some of which may
be strong to intense.

...20z Update...
The previous forecast remains mostly on track with only minor
adjustments made. Across the Midwest, latest GOES imagery shows
gradual clearing across southern IA/northern MO/western IL behind a
decaying MCS. Surface observations across southern IA show some
degree of air mass recovery is ongoing; however, the quality of
destabilization with northeastward extent remains very uncertain
given more extensive cloud cover, additional precipitation, and the
rapid approach of the cold front from the west.

Nonetheless, regional 18z RAOBs and VWPs are sampling the approach
of a 60-70 knot mid-level jet, which heralds the onset of stronger
synoptic ascent across the upper MS Valley. Southerly low-level flow
should strengthen through the evening in response to increasing
ascent, which will likely help advect higher theta-e air
north/northeastward as well as begin to augment low-level SRH.
Recent MRMS composites show the onset of convective initiation along
the cold front, which should maintain sufficient residence time
within the returning theta-e plume for further strengthening over
the coming hours. Latest high-res ensemble guidance (including WoFS
and time-lagged HRRR/RRFS solutions) appear to be capturing these
trends well and continue to depict the corridor of highest severe
wind and tornado threat across the Moderate risk zone. As such,
little change was made to the ongoing probability and intensity
contours.

...Upper OH Valley/Mid-Atlantic...
Several loosely organized convective bands have emerged across
eastern OH into western PA/NY. Regional VWPs continue to sample
deep-layer bulk shear on the order of 15-20 knots, which casts doubt
on the eastward extent of the severe wind threat beyond 00-02 UTC
when nocturnal stabilization will begin to weaken convection. Recent
CAM guidance suggests the peak wind threat should remain across
western to central PA/NY, which casts considerable uncertainty on
severe wind coverage further east along the Mid-Atlantic coast.
Consequently, the 30% wind probabilities have been shifted west to
better align with recent observed and modeled trends. (See MCDs
#1091 and #1092 for additional details.)

...Southern Plains...
Recent surface observations show the cold front rapidly pushing
southeast across TX, OK, and southeast KS. Building cumulus is also
noted along the front, which suggests convective initiation is
probable in the coming hours. These trends align with the previous
forecast, see MCD #1090 for additional short-term details.

..Moore.. 06/11/2026

.PREV DISCUSSION... /ISSUED 1122 AM CDT Thu Jun 11 2026/

...Midwest/Great Lakes...
An active and impactful severe weather event is still expected
across parts of the Midwest Great Lakes later this afternoon and
evening. Ongoing bowing cluster across southeast IA/northwest
IL/southwest WI and vicinity may continue to pose at least some
severe wind and embedded QLCS tornado threat as it continues
east-northeastward across parts of the Midwest this afternoon. There
is still airmass recovery underway ahead of this activity,
especially into central/northern IL, northern IN, and parts of
southern Lower MI where strong heating is occurring. Enhanced
mid-level west-southwesterly winds associated with a potent
shortwave trough over the northern Plains/Upper Midwest will
overspread the developing warm sector this afternoon, and support
organized severe potential, including the possibility of multiple
tornadic supercells and widespread severe/damaging winds.

Even so, greater than usual uncertainty exists regarding
redevelopment later today on the southern/western flank of ongoing
convection across northern IL into northeast MO and vicinity. A
gradual increase in both low-level and deep-layer shear is
anticipated across this area as a 30-40+ kt southerly low-level jet
develops eastward in tandem with the eastward-ejecting shortwave
trough and mid-level jet. A mix of supercells and bowing segments
appears probable as renewed thunderstorms develop along/ahead of the
surface cold front this afternoon in a strongly unstable and rather
favorably sheared environment. If at least semi-discrete supercell
structures can be maintained, then potential exists for several
tornadoes, and multiple strong to intense tornadoes (EF-2/3+) given
the enhanced low-level shear. Isolated large to very large hail may
also occur with any sustained supercells.

Otherwise, numerous to potentially widespread severe/damaging winds
also appear likely through the period across parts of
northern/central IL into southern Lower MI and northern IN. Both the
ongoing cluster and eventual upscale growth of convection that
develops this afternoon will likely produce severe/damaging winds,
some of which could be significant (75+ mph). The northern extent of
the severe risk into WI and northern Lower MI remains uncertain, but
at least some wind and/or tornado threat will likely continue with
eastward extent into the southern Great Lakes and northern IN this
evening.

...Eastern Kansas/Southern Missouri into the Southern Plains...
Additional thunderstorms will likely develop this afternoon and
evening along the trailing cold front into portions of eastern
KS/southern MO into the southern Plains. Stronger deep-layer shear
is forecast to lag behind/to the north of the cold front. Still,
around 20-30 kt of effective bulk shear and moderate to strong
instability will support marginal supercell structures and loosely
organized multicells capable of producing both large hail and
damaging winds. A large component of boundary-parallel shear will
likely lead to clustering and messy convective modes through the
evening before thunderstorms gradually weaken with the loss of
daytime heating.

...Mid-Atlantic/Central Appalachians...
Recent visible satellite imagery across much of the Mid-Atlantic and
central Appalachians shows mostly sunny to partly cloudy conditions,
with ample low-level moisture present per latest surface
observations and area 12Z observed soundings. Large-scale ascent
associated with multiple low-amplitude mid-level shortwave troughs
will likely support the development of widely scattered
thunderstorms by afternoon across parts of the Mid-Atlantic into the
central Appalachians. Though deep-layer shear is forecast to remain
modest, moderate to strong instability will exist with continued
diurnal heating this afternoon. This will support stronger updrafts
capable of scattered severe/damaging winds and perhaps isolated
hail. Multiple clusters should eventually emerge, with potential for
organizing along outflow/cold pools, and more focused corridors of
damaging winds possible across parts of the I-95 corridor from
northern VA to eastern PA and NJ.

$$

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ACUS01 KWNS 120102
SWODY1
SPC AC 120100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Thu Jun 11 2026

Valid 120100Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST/GREAT LAKES...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
MID ATLANTIC...

...SUMMARY...
Severe thunderstorms will continue this evening across parts of the
Midwest and Great Lakes region. This includes the potential for
tornadoes (possibly strong), widespread/intense damaging winds (some
75+ mph), and isolated hail.

...Parts of the Midwest/Great Lakes...
A rather volatile environment remains in place this evening across
parts of IL/IN and southwest Lower MI, especially in the vicinity of
a modified outflow across northern IL/IN. Rich low-level moisture,
moderate to strong buoyancy, and strong low-level shear/SRH will
continue to support all severe hazards through much of the evening.
Convection has largely taken on a linear or cluster mode, with an
attendant threat of severe/damaging gusts and line-embedded
tornadoes. Any discrete cells that can be maintained within or ahead
of ongoing convection will continue to pose a conditional
strong-tornado threat, along with isolated hail potential. See MCD
1101 and MCD 1102 for more information regarding the short-term
threat in this area.

Increasing CINH and decreasing MLCAPE with eastward extent should
eventually result in a weakening trend, though an organized severe
threat may reach parts of southeast MI and western OH later tonight.


...OK/TX into MO/northern AR...
Scattered strong to locally severe storms are ongoing from parts of western/central OK into MO, generally along or just behind a
southward moving cold front. Moderate to strong buoyancy and
deep-layer shear of around 25-35 kt near the front will continue to
support occasional storm organization and a continued threat of hail
and localized severe gusts, though convection may increasingly
become undercut by the front with time. An isolated severe threat
may eventually spread toward the Red River into western/northern AR
late tonight.

...Mid Atlantic vicinity...
Loosely organized storm clusters with a history of producing wind
damage are approaching the Mid Atlantic coast this evening. While
deep-layer shear will continue to be modest at best, a very
warm/moist boundary layer and moderate buoyancy will continue to
support potential for strong to locally severe gusts and scattered
wind damage, before convection weakens and/or moves offshore later
tonight.

..Dean.. 06/12/2026

$$

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ACUS01 KWNS 120601
SWODY1
SPC AC 120559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Fri Jun 12 2026

Valid 121200Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE APPALACHIANS...MID ATLANTIC...AND NORTHEAST...AND ALSO FOR PARTS OF
THE SOUTH-CENTRAL HIGH PLAINS...

...SUMMARY...
Strong to severe storms capable of damaging winds are possible
across parts of the Appalachians, Mid Atlantic, and Northeast,
mainly this afternoon and evening. Severe storms with a threat of
hail and severe gusts will also be possible across parts of the
south-central High Plains.

...Appalachians into the Mid Atlantic and Northeast...
A vigorous mid/upper-level shortwave trough is forecast to move
across Quebec later today, with weak midlevel height falls forecast
to extend south of this shortwave into parts of the Appalachians,
Northeast, and Mid Atlantic. The strongest deep-layer flow will
remain north of the international border, but modest effective shear
(generally 20-30 kt) will overlap relatively strong heating and
modest buoyancy across parts of the Northeast/Mid Atlantic.
Scattered outflow-driven clusters may develop with time and move
eastward, with an attendant threat of damaging wind and perhaps
isolated hail.

Deep-layer flow/shear will be even weaker into parts of the southern
Mid Atlantic/Carolinas vicinity. However, very strong heating of a
moist airmass will support potential for scattered thunderstorms
with downburst potential, and eventual evolution into loosely
organized clusters capable of damaging outflow winds from afternoon
into at least the early evening.

...South-central High Plains vicinity...
Moist southerly low-level flow beneath steepening midlevel lapse
rates will result in robust destabilization from the Raton Mesa
vicinity into the adjacent south-central High Plains, with MLCAPE
increasing to near/above 2000 J/kg by late afternoon. Modest
westerly mid/upper-level flow will support effective shear of 30-35
kt, conditionally supportive of organized convection. Large-scale
ascent will remain subtle, but eventual storms may develop by late
afternoon near the higher terrain, and spread east-southeastward
with time.

Initial storms could evolve into isolated supercells, with a threat
of hail, localized severe gusts, and possibly a tornado.
Consolidating outflow and a nocturnally strengthening low-level jet
will support some upscale growth during the evening, with an
attendant severe-wind threat expected to spread across parts of the south-central High Plains.

Farther south, more isolated strong to severe storms will be
possible across parts of central/eastern NM into Far West TX, with a
threat of isolated hail and localized severe gusts.

...Upper Midwest...
Relatively low-topped convection may develop late this afternoon
from the eastern Dakotas into MN, as low-level lapse rates steepen
beneath seasonably cool temperatures aloft. Robust
west-northwesterly flow aloft will conditionally favor some storm
organization, if sufficient buoyancy can develop. However, most
guidance depicts MLCAPE generally below 500 J/kg, with an
inconsistent signal for where the deepest convection might develop.
Some threat for marginal hail and/or locally damaging wind could
evolve across some part of this region, and probabilities may be
needed if confidence increases regarding sufficient destabilization
and storm coverage.

...Parts of NE into western IA...
Elevated convection may develop late in the period from parts of NE
into western IA, within a warm-advection regime to the north of a
warm front. Guidance continues to vary regarding the magnitude of
elevated moistening/destabilization (which may be affected by MCS
development to the south across KS) and coverage of storms prior to
the end of the forecast period. Effective shear will be sufficient
for at least modest storm organization and an isolated hail threat,
if sufficient destabilization can occur. The aforementioned
uncertainties and likely very late timing of any severe threat
preclude the addition of hail probabilities at this time.

...Parts of OK/north TX...
In the wake of morning convection, robust redevelopment cannot be
ruled out across parts of OK/north TX, near a outflow-influenced
surface boundary. Guidance varies substantially regarding the
coverage/location of storms through mid morning, resulting in
considerable uncertainty. Moderate to strong buoyancy and modest
deep-layer shear could result in localized hail/wind potential, but
confidence in boundary placement and diurnal storm coverage is too
low for probabilities at this time.

..Dean/Weinman.. 06/12/2026

$$

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