ACUS48 KWNS 310852
SWOD48
SPC AC 310850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Tue Mar 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
Severe weather potential will persist through the remainder of the
work week and into parts of the weekend as an amplified upper wave
and attendant surface low traverse the country. The cold front
associated with the late-week storm system will most likely push
south into the Gulf by Sunday as high pressure builds across the
eastern two-thirds of the country and short-wave ridging builds
aloft. This will likely limit the potential for widespread severe
thunderstorms for the early portion of next week.

...D4/Friday - Lower Missouri Valley into the southern Plains...
The approach of an upper wave into the central U.S. will support
steady intensification of a surface low across eastern KS and into
the lower MO River Valley through the day Friday. This will support
a northward flux of low to mid 60s dewpoints through the day, which
should yield SBCAPE values on the order of 2000 to perhaps 3000 J/kg
across northern OK into eastern KS and far western MO by late
afternoon based on a consensus of model solutions. Thunderstorm
development is expected as a cold front slowly begins to push
southeast and overtakes a surface trough/dryline. Deep-layer shear
vectors and storm motions off the boundary should promote initially
discrete cells, though upscale growth is anticipated by the evening
hours amid persistent ascent along the front. Regardless, long-range
guidance has shown a consistent signal for a robust convective
environment over the past 48 hours, and the favorable alignment of
both deterministic and ensemble guidance lends high confidence in a
severe threat emerging across this region Friday afternoon and
evening.

...D5/Saturday - Midwest/OH Valley...
Friday's surface low will continue to deepen as it accelerates
northeastward into the Midwest and Great Lakes by late Saturday.
Northward moisture advection is expected ahead of a trailing cold
front as it rapidly shifts east across the Midwest and lower OH
Valley through the afternoon. Strong flow fields within the lowest
few kilometers and focused lift along the front will likely support
some degree of a severe wind threat. However, guidance continues to
show disagreement regarding mean wind vector orientation with the
front and the degree of pre-frontal destabilization, both of which
will influence the intensity of convection and the overall severe
threat.

..Moore.. 03/31/2026

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ACUS48 KWNS 010829
SWOD48
SPC AC 010827

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0327 AM CDT Wed Apr 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
Some degree of severe thunderstorm potential is expected to persist
through the upcoming weekend across portions of the Great Lakes/OH
Valley and possibly across the Mid-Atlantic. Heading into next week,
a combination of building surface high pressure behind a synoptic
cold front and the re-establishment of an upper ridge over the West
will limit severe weather chances.

...D4/Saturday - Great Lakes/OH Valley...
An upper wave and attendant surface low are forecast to quickly
translate from the Plains into the Great Lakes region late Friday
through Saturday. Moisture return immediately ahead of a trailing
cold front will likely support some degree of destabilization
Saturday afternoon across the Great Lakes/OH Valley; however,
long-range ensemble guidance does not show high probability in surface/mixed-layer buoyancy values exceeding 1000 J/kg.
Nonetheless, strong flow within the lowest 1-2 km will likely
support a severe wind threat with any convection that can become
sufficiently intense. While some severe risk is anticipated, the
combination of a modest thermodynamic environment and disagreement
regarding the timing/progression of the front through peak heating
precludes risk probabilities.

...D5/Sunday - Mid-Atlantic...
The synoptic cold front is forecast to push off the East Coast by
late Sunday, though long-range guidance shows disagreement regarding
the timing of the front. Slower solutions, such as the 00z ECMWF,
suggest that the frontal passage may occur during the afternoon
hours when diurnal destabilization will be greatest. Strong
low-level flow coupled with robust broad-scale ascent ahead of the
primary upper wave may support a band of strong to severe
thunderstorms. However, the general consensus among guidance at this
time is that this scenario is likely the outlier solution.

..Moore.. 04/01/2026

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ACUS48 KWNS 020835
SWOD48
SPC AC 020833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Apr 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
Severe weather potential will be limited for late weekend and into
the upcoming work week based on trends in latest guidance. A strong
synoptic cold front is forecast to push from the Appalachians and
lower MS Valley east/southeastward towards the East Coast and
northern Gulf through the day Sunday. While some severe threat may
materialize across the Carolinas and Mid-Atlantic Sunday afternoon,
it will be conditional on favorable timing of the frontal passage
with the diurnal heating maximum. The frontal passage will shunt
appreciable low-level moisture offshore by early Monday. Building
surface high pressure over the central to eastern CONUS through
early week will maintain dry and stable conditions east of the
Rockies. Additionally, the amplification of an upper ridge over the
West will limit thunderstorm chances across the Intermountain West.
This synoptic regime will limit moisture return back into the Plains
with most guidance suggesting that appreciable moisture return (55+
dewpoints) may not return to the Plains until the D8/Thursday time
frame. Consequently, the potential for severe convection will be
limited through at least the middle of the upcoming week.

..Moore.. 04/02/2026

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ACUS48 KWNS 030822
SWOD48
SPC AC 030821

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0321 AM CDT Fri Apr 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
From Monday to Wednesday, a relatively dry and cool airmass is
forecast to settle in across the continental U.S. For this reason,
thunderstorm potential will be low over most of the nation.

...Thursday/Day 7 to Friday/Day 8...
A large area of surface high pressure is forecast to move eastward
in the western Atlantic by Thursday, as moisture return takes place
into the south-central states. Scattered thunderstorm development
will be possible during the day from the southern and central Plains
eastward into the lower to mid Mississippi Valley. A chance for
thunderstorms will continue into Friday over the same general area
as moisture advection continues. An isolated severe threat will be
possible each afternoon and evening, but the confidence in the
spatial distribution regarding any potential threat is low at this
time.

..Broyles.. 04/03/2026

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ACUS48 KWNS 040846
SWOD48
SPC AC 040844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Sat Apr 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
A large area of surface high pressure will settle in across the
continental U.S. on Tuesday and Wednesday. The associated dry and
cool airmass will limit thunderstorm potential in most areas.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, a cold front is forecast to move southward into the
central Plains and stall, as moisture advection takes place to the
south of the front over much of the southern Plains. A dryline is
forecast to setup over west Texas Thursday afternoon. Thunderstorm
development will be likely along parts of the front and to the east
of the dryline. An isolated severe threat will be possible in the
afternoon and evening. Models differ considerably on the
distribution of instability, with some suggesting that instability
will remain relatively weak. This would keep any severe threat
marginal in most areas.

On Friday and Saturday, a moist and unstable airmass is forecast to
be in place over the southern half of Texas, as a shortwave trough
moves northeastward across the region. Lift associated with this
feature would support scattered thunderstorm development. The
greatest severe potential both Friday and Saturday appears to be
across south-central Texas, where the models have moderate
deep-layer shear and sufficient instability. At this extended range, uncertainty concerning magnitude and spacing is substantial.

..Broyles.. 04/04/2026

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ACUS48 KWNS 050850
SWOD48
SPC AC 050848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sun Apr 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
...Wednesday/Day 4 and Thursday/Day 5...
From Wednesday into Thursday, an upper-level trough will move from
the High Plains into the Great Lakes, as a large area of surface
high pressure moves across the eastern U.S. Along the western edge
of this feature on Thursday, low-level moisture advection is
forecast from the southern and central Plains into the lower to mid
Mississippi Valley. Within this returning airmass, isolated to
scattered thunderstorms will be possible Thursday afternoon and
evening. The best chance for severe storms would be across parts of
the central Plains, as the low-level jet ramps up in the evening.
Uncertainty exists concerning the magnitude of any potential severe
threat.

...Friday/Day 6 to Sunday/Day 8...
Moisture advection is forecast to continue on Friday over the
southern Plains and Ark-La-Tex, as surface dewpoints increase into
the 60s F. A slow-moving cold front is forecast to stall in the
central Plains, which would be a focus for thunderstorm development.
Isolated to scattered storms are also expected on Friday along and
to the east of a dryline in the southern High Plains. An isolated
severe threat would be possible in areas that sufficiently
destabilize. The potential for severe storms should continue into
Saturday and Sunday over the southern and central Plains, as an
upper-level trough moves across the region. At this time, model
spread is substantial concerning the magnitude and spatial
distribution of instability. The models also vary widely on the
timing and amplitude of the shortwave trough. For these reasons,
will hold off introducing a threat area until the models can show
better agreement.

..Broyles.. 04/05/2026

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ACUS48 KWNS 060835
SWOD48
SPC AC 060834

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0334 AM CDT Mon Apr 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
From Thursday to Saturday, mid-level flow over the south-central
U.S. is forecast to gradually transition from westerly to
southwesterly. In response, low-level moisture advection will likely
take place in the southern and central Plains. Isolated severe
storms will be possible near a front in the central Plains from late
Thursday afternoon into the early overnight period, as a low-level
jet strengthens. On Friday, weak instability is forecast to develop
over much of the southern Plains. Isolated to scattered
thunderstorms will be possible in the afternoon and evening across
parts of this airmass. An isolated severe threat may develop in some
areas, but deep-layer shear is forecast to be relatively weak over
much of the southern Plains, suggesting a more localized severe
potential.

On Saturday, the potential for severe storms is expected to increase
over parts of southern High Plains, as mid-level southwesterly flow strengthens. Model consensus suggests that the greatest severe
threat potential will be over parts of west Texas, where some models
have an axis of moderate instability in place by late Saturday
afternoon. Supercells with large hail and severe wind gusts will be
possible in the afternoon and evening, with storms that develop near
this instability axis.

...Sunday/Day 7 and Monday/Day 8...
On Sunday, an upper-level low and an associated trough is forecast
to move eastward across the Desert Southwest and northern Mexico.
Ahead of this trough, moderate instability is forecast to develop by
Sunday afternoon over much of the southern High Plains. Scattered
severe storms would be possible to the east of a west Texas dryline
in the afternoon and evening. A severe threat should continue into
the overnight as a low-level jet strengthens ahead of the
approaching trough.

On Monday, the upper-level trough is forecast to move quickly
northeastward across the central U.S, with an axis of moisture and
instability located in the Great Plains. Scattered severe storms
will be possible from Monday into Monday night from the southern
Plains northward into Upper Midwest. At this extended range, there
is still considerable uncertainty concerning the timing of the
trough. For this reason, will hold off on a threat area until the
models show better agreement.

..Broyles.. 04/06/2026

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ACUS48 KWNS 070858
SWOD48
SPC AC 070856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Tue Apr 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...Friday/Day 4 to Sunday/Day 6...
An upper-level trough will move eastward from the eastern Pacific on
Friday into the western U.S. on Saturday, as southwest mid-level
flow gradually strengthens over the south-central states. In
response, low-level moisture advection will continue over the Great
Plains. Ahead of the western U.S. trough, a subtle shortwave trough
is forecast to move into the southern High Plains Saturday
afternoon. A severe threat will be possible ahead of and near the
trough during the afternoon and evening.

On Sunday, the western U.S. upper-level trough is forecast to move
quickly east-northeastward into the southern Rockies. Ahead of the
trough, a moist and moderately unstable airmass is forecast over
much of the southern and central Plains by afternoon. Scattered
thunderstorms appear likely to develop over much of this airmass
during the afternoon and evening. Moderate to strong deep-layer
shear appear likely to be in place, which will be favorable for
severe storms. Supercells with large hail, severe wind gusts and a
tornado threat will be possible. An isolated severe threat may also
develop in parts of the north-central U.S.

...Monday/Day 7 and Tuesday/Day 8...
A secondary upper-level trough is forecast to move into the Desert
Southwest on Monday. Ahead of this system, a moist and unstable
airmass is forecast to remain in place from the southern Plains north-northeastward into the Upper Midwest. Although a severe threat
will be possible along much of the instability corridor, the
greatest threat is expected to develop in the southern Plains, where
model forecasts show the most favorable environment.

On Tuesday, model forecasts have some agreement concerning the
timing of the trough, which is forecast to eject northeastward
across the southern and central Plains. Ahead of the trough, there
is large variance among the models concerning the distribution of
instability. If a moderately unstable airmass is in place by Tuesday
afternoon ahead of the ejecting system, a severe threat will be
likely from the southern Plains into the mid to upper Mississippi
Valley. However, the system will probably be slower than forecast,
which adds considerable uncertainty this late in the period.

..Broyles.. 04/07/2026

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ACUS48 KWNS 080856
SWOD48
SPC AC 080854

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Wed Apr 08 2026

Valid 111200Z - 161200Z

...DISCUSSION...
...Saturday/Day 4 to Monday/Day 6...
On Saturday, mid-level southwesterly flow will strengthen over the
central U.S., as an upper-level system moves to near the West Coast.
A moist airmass will be in place over the southern and central
Plains, as a low-amplitude shortwave trough moves across the region. Large-scale ascent along with warming surface temperatures will
result in scattered thunderstorm development over much of west Texas
Saturday afternoon. MLCAPE is expected to peak near 1000 J/kg in
some areas, with 0-6 km shear being in the 30 to 40 knot range over
much of the southern High Plains. This should be sufficient for a
severe threat, with large hail and severe wind gusts possible.

From Saturday night into Sunday, strong moisture advection is
forecast over the Great Plains. By Sunday afternoon, moderate
instability is expected to be in place over much of this airmass.
Isolated to scattered severe thunderstorms are expected throughout
much of the moist sector during the afternoon and evening. Some
model forecasts move a 50 to 60 knot mid-level jet through central
and northeast Texas during the afternoon and evening. If this
happens, then a substantial severe threat would be possible from
parts of central and north Texas into Oklahoma. Severe storms,
including supercells with large hail, wind damage and a tornado
threat would be possible in areas that destabilize the most.

On Monday, a moist and unstable airmass is forecast to remain from
the southern Plains extending north-northeastward into the Upper
Midwest. Strong to severe thunderstorm development will be possible
over much of the instability corridor in the afternoon and evening.
The greatest potential for severe storms is forecast from the
southern Plains north-northeastward into the lower Missouri Valley
and upper Mississippi Valley, where the models develop moderate
instability and have 0-6 km shear mostly in the 30 to 40 knot range.
Severe storms with large hail, wind damage and a tornado threat will
be possible.

...Tuesday/Day 7 and Wednesday/Day 8...
The western U.S. trough is finally forecast to approach the southern
Plains on Tuesday, where a moist and unstable airmass should be in
place. Some solutions suggest that a mid-level jet will move into
the southern Plains Tuesday afternoon. This would create strong
deep-layer shear over parts of the moist sector, suggesting that a
substantial severe threat will be possible. Although there is still
spatial uncertainty regarding this scenario, current model forecasts
would support supercells with large hail, severe wind gusts and some
tornadoes.

On Wednesday, a shortwave trough is forecast to move through the
central states, with a southwest-to-northeast corridor of moderate
instability in place by afternoon from northeast Texas into western
Ozarks. This would be favorable for severe storms. However, at this
extended range, considerable uncertainty exists concerning severe
threat magnitude and spacing.

..Broyles.. 04/08/2026

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ACUS48 KWNS 090900
SWOD48
SPC AC 090858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Thu Apr 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
...Sunday/Day 4 to Tuesday/Day 6...
On Sunday, southwesterly mid-level flow will be in place across much
of the nation. At the surface, a moist airmass will be located from
the southern Plains north-northeastward into the Upper Midwest. Much
of this corridor is forecast to become moderately unstable by
afternoon. The greatest potential for severe storms will likely be
in the southern and central Plains, where some solutions have a
subtle shortwave trough. Moderate deep-layer shear and steep lapse
rates will be favorable for supercells with large hail and severe
wind gusts.

Mid-level flow is forecast to gradually strengthen across the
central U.S. on Monday. In response moisture advection will continue
in the Great Plains. By Monday afternoon, moderate instability
should be in place from north Texas northward into the upper
Mississippi Valley. Isolated to scattered thunderstorms are expected
to develop across this airmass Monday afternoon and evening.
Moderate deep-layer shear and steep lapse rates will again be
favorable for severe storms capable of large hail and severe wind
gusts. A tornado threat may also develop.

On Tuesday, an upper-level trough is forecast to move eastward into
the southern Rockies, as an associated mid-level jet streak ejects northeastward across the southern High Plains. A moderately unstable
airmass will likely be in place by afternoon from the southern
Plains northeastward into mid to upper Mississippi Valley and
southern Great Lakes. Strong deep-layer shear is forecast over the
southern and central Plains, where a substantial severe threat will
be possible. Supercells with large hail, wind damage and tornadoes
are expected Tuesday afternoon and evening. An upgrade will be
possible across parts of the threat area, once confidence increases
on the timing of the ejecting trough.

...Wednesday/Day 7 and Thursday/Day 8...
The upper-level trough is forecast to move eastward across the
central U.S. on Wednesday, as a cold front advances southeastward
through the Great Plains and Upper Midwest. Moderate instability is
forecast to develop ahead of much of the front. Thunderstorms that
form in areas that destabilize sufficiently could have a severe
threat. The severe potential will likely continue into Thursday, as
the front advances southeastward into the mid Mississippi Valley.
However, model spread concerning the position of the front and
timing of the trough increases substantially toward mid week,
suggesting a lot of uncertainty exists at this extended range in the
period.

..Broyles.. 04/09/2026

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ACUS48 KWNS 100830
SWOD48
SPC AC 100828

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0328 AM CDT Fri Apr 10 2026

Valid 131200Z - 181200Z

...DISCUSSION...
...Days 4-6/Mon-Wed -- Central/Southern Plains to the Midwest...

There is quite a bit of uncertainty regarding severe
potential/evolution during the Monday-Wednesday period. An upper
trough will slowly pivot across the West on Monday, and emerge over
the central/southern Rockies by early Wednesday before finally
ejecting across the Plains and toward the Mid/Upper MS Valley on
Wednesday. During this time, broad southwesterly deep-layer flow
will overspread the Plains into the Mid/Upper MS Valley.

On Monday, a surface low will develop over the northern/central
Plains, with a dryline extending southward across KS/OK/TX and a
warm front extending across southern MN/WI. Several lead shortwave
impulses will move across the Plains, though height tendencies will
remain mostly neutral. Nevertheless, cooling aloft will support
steep midlevel lapse rates and increasing boundary layer moisture
(surface dewpoints in the low/mid 60s F) will support moderate to
strong destabilization. During the evening, a southwesterly
low-level jet will increase across the Plains, overspreading the
surface dryline. Vertically veering wind profiles and 30-40 kt
effective shear magnitudes would support supercells capable of all
hazards, though storm coverage remains uncertain.

By Tuesday, the GFS becomes more progressive with the western
trough, ejecting it into the Plains by early Wednesday, whereas the
ECMWF hangs the trough back west and is slower. Nevertheless, a
similar airmass will be in place across the warm sector east of a
dryline across the Plains and to the south of a warm front draped
across the Great Lakes. Isolated convection may develop along the
dryline across the Plains, posing a supercell/all-hazards risk.
Higher storm coverage appears more likely across portions of the
Mid/Upper MS Valley/Great Lakes vicinity closer to a surface low.

On Wednesday, the upper trough should progress from the Plains to
the Great Lakes while weakening some. A surface cold front will
develop southeast across portions of the central U.S. and some
severe risk should persist along/ahead of this boundary. How
convection evolves on Tuesday into Wednesday will impact where the
greatest severe risk will develop, but at least some risk should
exist from portions of the southern Plains to the Mid-MS Valley.

...Days 7-8/Thu-Fri...

Predictability is low heading into the end of the forecast period on
Thursday and Friday as large spread exists among medium range
guidance. However, western U.S. upper troughing may persist,
suggesting some severe thunderstorm potential could persist for
parts of the Plains late in the work week.

..Leitman.. 04/10/2026

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ACUS48 KWNS 110846
SWOD48
SPC AC 110844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Sat Apr 11 2026

Valid 141200Z - 191200Z

...DISCUSSION...
...Day 4/Tue -- Southern Plains to Great Lakes...

A shortwave upper trough embedded within the larger-scale western
U.S. trough will eject across portions of the Plains to the Upper
Midwest on Day 4/Tue. As this occurs, a surface low will deep over
the central Plains and lift northeast across the Upper Midwest/Great
Lakes. Some uncertainty remains regarding the exact evolution of
this system, mainly due to differences in medium range guidance with
respect to surface low placement and timing of the upper shortwave
trough. Nevertheless, a moist and unstable airmass is expected ahead
of the low and to the east of a Plains dryline and south of a Great
Lakes warm front. Thunderstorm development should be more widespread
along these boundaries compared to prior days given stronger
large-scale ascent will overspread the central U.S., and height
falls will result in a more robust low-level jet response. As a
result, an all-hazards severe event is expected from the southern
Plains into portions of the Upper Midwest/Great Lakes vicinity on Tuesday/Tuesday night.

...Day 5/Wed -- Southern Plains to the Midwest...

Medium range guidance varies heading into Wednesday with the
operational GFS much more progressive and lower amplitude than the
operational ECMWF. The AIGFS is much more in-line with the
ECMWF/AIFS, so this period is weighted more toward those solutions.
It appears the upper trough over the southern Rockies will eject
across the Plains to the Mid-MS Valley during this time. A moist and
unstable airmass will reside across the region ahead of dryline
across western OK into central TX and a sagging cold front across
the Lower MO/Mid-MS Valley. Areas of precipitation could be ongoing
at the beginning of the period and does result in some uncertainty
regarding where stronger destabilization will occur. Nevertheless,
an overall favorable thermodynamic/kinematic parameter space will
overlap this corridor and isolated to scattered severe storms appear
likely.

...Days 6-8/Thu-Sat...

Medium range guidance depicts another trough developing across the
West on Day 6/Thu and quickly progressing east through the end of
the period. This could support a continued severe risk across parts
of the southern Plains into the Midwest in the Thursday or Friday
time frame. However, run to run consistency toward the end of the
forecast period has not been very good. Additionally, multiple
rounds of storms across the same areas earlier in the period may
impact later severe potential. Trends will be monitored and
probabilities may be needed in later outlooks.

..Leitman.. 04/11/2026

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ACUS48 KWNS 120841
SWOD48
SPC AC 120839

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0339 AM CDT Sun Apr 12 2026

Valid 151200Z - 201200Z

...DISCUSSION...
...Day 4/Wed - Southern Plains to southern Wisconsin...

An upper trough will be oriented over the central/southern High
Plains Wednesday morning. This feature will shift east to the
Mississippi River by Thursday morning. As this occurs, strong
deep-layer southwesterly flow will overspread a moist and unstable
airmass from TX toward the Great Lakes. Some convection may be
ongoing Wednesday morning, resulting in some uncertainty regarding
airmass recovery and convective evolution during the
afternoon/evening. However, persistent southerly low-level flow
ahead of a dryline and continued warm advection should support areas
of airmass recovery. A mix of supercells and linear segments will be
possible, posing an all-hazards severe risk.

...Day 5/Thu...

Severe potential should be lower on Thursday as the upper trough and
weakens at it shifts east across the Ohio Valley. Widespread showers
and thunderstorms will be possible from parts of the Great
Lakes/Ohio Valley into the TN Valley, with modest instability and
limited heating tempering severe potential.

...Day 6/Fri - Southern Plains to Upper Midwest...

Medium range guidance has been fairly consistent the past several
forecast cycles in bringing a large-scale upper eastward from the
Rockies into the Plains Friday/Friday night. This should result in
surface cyclogenesis across portions of the Upper Midwest with a
trailing cold front extending into the southern Plains. Ahead of the
front, a seasonally moist/unstable airmass will be in place beneath strengthening southwesterly deep-layer flow. This should support a
severe risk ahead of the front.

...Days 7-8/Sat-Sun...

The upper trough will continue east over the eastern U.S. on
Saturday and Sunday. Stronger ascent will shift northeast into
Canada. Deep-layer flow parallel to the surface front and a
narrowing warm sector should limit severe potential.

..Leitman.. 04/12/2026

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ACUS48 KWNS 130846
SWOD48
SPC AC 130844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Mon Apr 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
...Day 4/Thu - Mid-South vicinity...

An upper shortwave trough will develop northeast from eastern OK/TX
to the central/southern Appalachians on Thursday. Convection is
likely to be ongoing from the Mid-MS/Lower OH Valley to the ArkLaTex
region Thursday morning. This will likely temper downstream
destabilization (and overall severe risk), but a few strong storms
are possible across the Mid-South vicinity.

...Day 5/Fri - Southern Plains to Iowa...

Medium range guidance has been consistently showing an upper trough
over the western U.S. developing eastward toward the High Plains
Friday/Friday night. As this occurs, increasing deep-layer
southwesterly flow will overspread a seasonally moist and unstable
airmass. A lee low will deepen over the central/southern High
Plains, with a dryline extending across western OK/TX during the
afternoon. By evening and into the overnight hours, a cold front
will spread southeast across the central/southern Plains and Lower
MO Valley. This pattern will support a risk of severe storms across
the warm sector from OK to IA.

...Days 6-8/Sat-Mon...

Some severe risk may persist into Saturday as a surface low deepens
over the Great Lakes and the cold front from the Day 5/Friday period
continues to sweep east across the Midwest to the Lower MS Valley,
becoming oriented across the Appalachians by Sunday morning. Severe
potential may depend on how convection on Friday evolves and impacts
the downstream airmass heading into Saturday morning, resulting in
low predictability at this time. Strong surface high pressure will
build across the Plains in the wake of the cold front, and Gulf
moisture will become cut-off as the front pushes well south into the
Gulf Basin. This should bring a reprieve from severe thunderstorm
potential Sunday into Monday as surface high pressure envelops much
of the CONUS east of the Rockies by the end of the period.

..Leitman.. 04/13/2026

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ACUS48 KWNS 140833
SWOD48
SPC AC 140831

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0331 AM CDT Tue Apr 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
...Day 4/Friday - Southern Plains to Upper Midwest...

A strong upper trough oriented from Montana to the Southwest will
eject eastward to the Plains on Friday/Friday night. Southwesterly
mid/upper flow will intensify ahead of this feature, with 40-60 kt
850-700 mb flow forecast by late afternoon into the nighttime hours.
A somewhat complex surface pattern is forecast, with a lee low
deepening over the central/southern High Plains to western OK, and a
second surface low near the Mid-Missouri Valley developing northeast
into Ontario. A surface dryline will extend from the High Plains low
to near the western OK/TX panhandle border into central TX by
midday. Meanwhile, a cold front will be oriented from eastern MN
into central KS at midday.

Ahead of these surface features, a broad warm sector characterized
by mid/upper 60s F dewpoints will be in place as temperatures warm
into the 80s F. A plume of steep midlevel lapse rates will
overspread the region, resulting in moderate to strong
destabilization. Forecast soundings indicated impressive wind
profiles supporting supercells. Initial supercell storms capable of
all hazards (including very large hail and strong tornadoes) are
expected. During the evening, convection may grow upscale into a
squall line as storms near the Mississippi River, with an
accompanying increase in damaging wind potential.

...Day 5/Saturday - Ohio Valley/Great Lakes vicinity...

A severe risk will likely continue into Saturday as the upper trough
continues to strengthen and shift east from the Plains to the Great Lakes/Midwest. Strong deep-layer flow parallel to an
eastward-advancing cold front will overspread a moist and at least
weakly unstable downstream airmass through evening. This will favor
a line of convection with damaging wind potential.

...Days 6-8/Sunday-Tuesday...

The surface cold front will continue east on Sunday, moving offshore
the Atlantic and Gulf coasts during the afternoon. Severe potential
appears limited by weak instability and mainly anafrontal
precipitation across the Southeast to Eastern U.S. on Sunday.
Surface high pressure and a dearth of boundary layer moisture in the
wake of the cold front will preclude thunderstorm activity on
Monday. By the end of the period, medium range guidance depicts
another upper trough moving into the western U.S. and Gulf return
flow will advect moisture back into the southern Plains. However,
severe thunderstorm potential appears low at this time.

..Leitman.. 04/14/2026

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ACUS48 KWNS 140848
SWOD48
SPC AC 140846

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0346 AM CDT Tue Apr 14 2026

Valid 171200Z - 221200Z

CORRECTED FOR DAY 5 GRAPHIC LABEL

...DISCUSSION...
...Day 4/Friday - Southern Plains to Upper Midwest...

A strong upper trough oriented from Montana to the Southwest will
eject eastward to the Plains on Friday/Friday night. Southwesterly
mid/upper flow will intensify ahead of this feature, with 40-60 kt
850-700 mb flow forecast by late afternoon into the nighttime hours.
A somewhat complex surface pattern is forecast, with a lee low
deepening over the central/southern High Plains to western OK, and a
second surface low near the Mid-Missouri Valley developing northeast
into Ontario. A surface dryline will extend from the High Plains low
to near the western OK/TX panhandle border into central TX by
midday. Meanwhile, a cold front will be oriented from eastern MN
into central KS at midday.

Ahead of these surface features, a broad warm sector characterized
by mid/upper 60s F dewpoints will be in place as temperatures warm
into the 80s F. A plume of steep midlevel lapse rates will
overspread the region, resulting in moderate to strong
destabilization. Forecast soundings indicated impressive wind
profiles supporting supercells. Initial supercell storms capable of
all hazards (including very large hail and strong tornadoes) are
expected. During the evening, convection may grow upscale into a
squall line as storms near the Mississippi River, with an
accompanying increase in damaging wind potential.

...Day 5/Saturday - Ohio Valley/Great Lakes vicinity...

A severe risk will likely continue into Saturday as the upper trough
continues to strengthen and shift east from the Plains to the Great Lakes/Midwest. Strong deep-layer flow parallel to an
eastward-advancing cold front will overspread a moist and at least
weakly unstable downstream airmass through evening. This will favor
a line of convection with damaging wind potential.

...Days 6-8/Sunday-Tuesday...

The surface cold front will continue east on Sunday, moving offshore
the Atlantic and Gulf coasts during the afternoon. Severe potential
appears limited by weak instability and mainly anafrontal
precipitation across the Southeast to Eastern U.S. on Sunday.
Surface high pressure and a dearth of boundary layer moisture in the
wake of the cold front will preclude thunderstorm activity on
Monday. By the end of the period, medium range guidance depicts
another upper trough moving into the western U.S. and Gulf return
flow will advect moisture back into the southern Plains. However,
severe thunderstorm potential appears low at this time.

..Leitman.. 04/14/2026

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ACUS48 KWNS 150755
SWOD48
SPC AC 150753

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 AM CDT Wed Apr 15 2026

Valid 181200Z - 231200Z

...DISCUSSION...
...Day 4/Sat - Ohio Valley...

An upper trough will overspread the Great Lakes and Midwest on
Saturday. At the surface, a cold front will sweep east across the
region during the day. Destabilization will likely be limited by
downstream cloud cover within a strong low-level warm advection
regime ahead of the front. Additionally, convection will likely be
ongoing in the vicinity of the front from Lower MI into IN/IL.
Nevertheless, strong mid/upper flow (40-60 kt in the 850-700 mb
layer) will support strong to severe convection even amid weak
instability. As such, a damaging wind gust risk will accompany
linear convection moving across the region during the day into
evening.

...Days 5-6/Sun-Mon...

Strong high pressure in the wake of the cold front from the Day 4
period will overspread much of the CONUS east of the Rockies early
next week. A dry/stable airmass will preclude thunderstorm
potential.

...Days 7-8/Tue-Wed...

An upper trough is forecast to develop across the western U.S. Tuesday/Wednesday. This will result in lee trough development across
the High Plains, and strengthening south/southeasterly low-level
flow will transport Gulf moisture northward across the southern
Plains. Medium range guidance varies on whether or not this western
trough will eject into the Plains during this time, or if upper
ridging will be maintained. If the trough ejects, severe potential
could develop across portions of the southern/central Plains
Tuesday/Wednesday, though predictability is too low at this time to
introduce severe probabilities.

..Leitman.. 04/15/2026

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ACUS48 KWNS 160840
SWOD48
SPC AC 160838

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CDT Thu Apr 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
Severe thunderstorm potential will be low through at least Day
6/Tuesday. In the wake of a cold front moving offshore the Atlantic
coast and into the Gulf, strong surface high pressure will build
east of the Rockies and persist across parts of the South and East
through Day 6/Tuesday. As a result, a dry and stable boundary layer
will preclude severe thunderstorm potential.

By the middle of the week, and upper trough is forecast to
overspread the western U.S. As this occurs, lee surface troughing
will allow for increasing southerly winds over the Plains, and Gulf
moisture will begin to return northward Days 7-8/Wed-Thu. It remains
uncertain if the upper trough will begin to eject eastward toward
the Plains at the end of the period. If this occurs, some severe
potential may develop across the Plains, though predictability is
low.

..Leitman.. 04/16/2026

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ACUS48 KWNS 170743
SWOD48
SPC AC 170741

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0241 AM CDT Fri Apr 17 2026

Valid 201200Z - 251200Z

...DISCUSSION...
A dry, continental airmass will persist across most of the CONUS for
the first part of next week. Severe weather chances will start to
increase by the middle of the week and into the later part of the
week. Forecast guidance consistently shows mid 60s F dewpoints
across the Plains and into the Midwest. However, aloft the pattern
remains quite uncertain. The ECMWF and the GEFS and EPS all show a
developing large-scale trough centered across the western CONUS with
multiple shortwave troughs which could result in severe weather
Day6/Wed to Day 8/Fri. However, the 00Z GFS and the EC-AIFS show a
consolidated mid-level trough which could result in a much more
substantial severe weather event across the central/southern Plains.
At this time, uncertainty is too high for specific risk areas, but
Day6/Wed to Day 8/Fri will likely feature multiple days of severe
weather across portions of the central/southern Plains.

..Bentley.. 04/17/2026

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