ACUS48 KWNS 131953
SWOD48
SPC AC 131951

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Fri Mar 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
Significant severe winds and the potential for a few tornadoes will
develop on Monday over parts of the Carolinas and Mid Atlantic.

Models are in good agreement with the large scale pattern on
Monday/D4, depicting a deep upper trough moving out of the
Mississippi Valley and ejecting in negative-tilt fashion across the
Mid Atlantic and into to the Northeast.

Given the antecedent upper ridging on the previous day, low-level
southerly winds will help to moisten the air mass well ahead of an
approaching cold front. By 12Z Monday, 60s F dewpoints will already
extend from northern GA across the Piedmont and into southeast VA,
and this plume of moisture will rapidly spread north with near 60 F
dewpoints into southeast PA by 00Z.

There appears to be two regimes for severe potential on Monday.
First, up to 1000 J/kg MUCAPE may develop well ahead of the
approaching cold front, and there is some indication that scattered
convection may occur across the warm sector from mid to late
afternoon. If this occurs, supercells would be most likely, with
potential for a few tornadoes from the Carolinas into eastern VA.

Models also indicate an elongated pressure fall/rise couplet, which
when combined with 50-70 kt 850 mb winds and extreme low-level
shear, could easily result in a QLCS along the cold front with
corridors of significant damaging winds and embedded tornado risk.

Beyond Monday/D4, stable air behind this system will likely preclude
any severe threat through Friday/D8.

..Jewell.. 03/13/2026

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ACUS48 KWNS 132006
SWOD48
SPC AC 132004

Day 4-8 Convective Outlook AMEND 1
NWS Storm Prediction Center Norman OK
0304 PM CDT Fri Mar 13 2026

Valid 161200Z - 211200Z

AMENDED TO EXPAND D4/MONDAY THREAT AREAS

...DISCUSSION...
...Updated discussion for D4...
The majority of deterministic and ensemble model guidance agree on a
deep midlevel trough and associated cold front that will move
eastward across the Appalachians and to the Atlantic coast by
Tuesday morning. Severe storms could be ongoing at the beginning of
the period along the northeast Gulf coast into GA. The warm sector, characterized by boundary-layer dewpoints in the 60s, will expand
northward (generally east of the Appalachians) through the day as
far north as PA. Though clouds could limit downstream surface
heating somewhat, very strong wind profiles and focused forcing for
ascent will favor a continuation of convection along the front, as
well as pre-frontal convection, with the potential to produce
relatively widespread damaging winds and several tornadoes.

...Previous discussion below...
Significant severe winds and the potential for a few tornadoes will
develop on Monday over parts of the Carolinas and Mid Atlantic.

Models are in good agreement with the large scale pattern on
Monday/D4, depicting a deep upper trough moving out of the
Mississippi Valley and ejecting in negative-tilt fashion across the
Mid Atlantic and into to the Northeast.

Given the antecedent upper ridging on the previous day, low-level
southerly winds will help to moisten the air mass well ahead of an
approaching cold front. By 12Z Monday, 60s F dewpoints will already
extend from northern GA across the Piedmont and into southeast VA,
and this plume of moisture will rapidly spread north with near 60 F
dewpoints into southeast PA by 00Z.

There appears to be two regimes for severe potential on Monday.
First, up to 1000 J/kg MUCAPE may develop well ahead of the
approaching cold front, and there is some indication that scattered
convection may occur across the warm sector from mid to late
afternoon. If this occurs, supercells would be most likely, with
potential for a few tornadoes from the Carolinas into eastern VA.

Models also indicate an elongated pressure fall/rise couplet, which
when combined with 50-70 kt 850 mb winds and extreme low-level
shear, could easily result in a QLCS along the cold front with
corridors of significant damaging winds and embedded tornado risk.

Beyond Monday/D4, stable air behind this system will likely preclude
any severe threat through Friday/D8.

..Thompson.. 03/13/2026

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ACUS48 KWNS 140851
SWOD48
SPC AC 140850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Sat Mar 14 2026

Valid 171200Z - 221200Z

...DISCUSSION...
On Tuesday/D4, a large upper trough will move across the Northeast,
though the associated surface cold front will already be well
offshore the East Coast with high pressure over land. Behind this
upper trough, models indicate a large upper ridge will be situated
over the Southwest for several days, with a northwest flow pattern
across the Plains. Given this pattern, minimal appreciable moisture
return is expected over the CONUS, and severe storms appear unlikely
through Saturday/D8.

..Jewell.. 03/14/2026

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ACUS48 KWNS 150852
SWOD48
SPC AC 150850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Sun Mar 15 2026

Valid 181200Z - 231200Z

...DISCUSSION...
Severe storms appear unlikely across the CONUS for the D4-8 period,
as an upper ridge holds over the Southwest with a mean upper trough
over the East. This pattern will keep a surface high over much of
the east/southeast CONUS, with northerly winds over the Gulf Of
America for much of the period.

Models do indicate the upper ridge over the Southwest may weaken
into the Sat/D7 and Sun/D8 time frame, with perhaps the pattern
trending toward zonal. Even so, potential for any significant
instability to develop over land remains minimal.

..Jewell.. 03/15/2026

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ACUS48 KWNS 160648
SWOD48
SPC AC 160646

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0146 AM CDT Mon Mar 16 2026

Valid 191200Z - 241200Z

...DISCUSSION...
A northwest flow regime will persist across the Plains through
Saturday/D6 as an upper high holds over the southwestern states. The
ridge is expected to break down late D6 through the remainder of the
period into Monday/D8, as a strong wave moves southeastward into the
Great Lakes, and a weaker wave potentially moves into the Great
Basin/Four Corners states on Sunday/D7. This overall pattern will
maintain relatively stable conditions over most of the CONUS, with
high pressure over the southeastern states including the Gulf of
America. Further, as the stronger wave potentially moves across the
Great Lakes and into the Northeast, a reinforcing cold front is
likely to plunge south over much of the central and eastern states
into the D7/D8 time frame. While limited moisture may precede this
cold front, overall potential for destabilization appears to be
minimal.

..Jewell.. 03/16/2026

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ACUS48 KWNS 170614
SWOD48
SPC AC 170612

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0112 AM CDT Tue Mar 17 2026

Valid 201200Z - 251200Z

...DISCUSSION...
An upper ridge will hold over the Southwest from Fri/D4 into Sat/D5,
but will begin to flatten as a progressive, low-amplitude wave moves
into the far northern Rockies and Plains. This feature is then
forecast to amplify across the Great Lakes and Northeast during the
Sun/D6 to Tue/D8 period, while an upper ridge possibly re-builds
over the Southwest. However, predictability becomes low for that
pattern change.

In association with the northern wave, low pressure with a trailing
cold front may develop from the Plains to the Mid Atlantic from
Sun/D6 into Mon/D7. Given the antecedent dry conditions, only
marginal moisture return and destabilization are expected. While
this may support scattered thunderstorms across the Ohio Valley
region on Sunday/D6, substantial severe weather is not anticipated.

Behind that system, a reinforcing high will likely spread south
across the Plains and much of the East, resulting in stable
conditions.

..Jewell.. 03/17/2026

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ACUS48 KWNS 180719
SWOD48
SPC AC 180717

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0217 AM CDT Wed Mar 18 2026

Valid 211200Z - 261200Z

...DISCUSSION...
An upper ridge is forecast to break down across the Southwest late
Saturday/D4 into Sunday/D5, with a weak wave embedded in the
northwesterly flow regime aloft. During the same time, a stronger
but low-amplitude feature will move rapidly east/southeast along the
Canadian border, across the Great Lakes and into the Northeast.

In association with the northern/Great Lakes disturbance, a cold
front is forecast to push south into the Plains on Sunday/D5,
extending into the OH Valley by late in the day. This front will
interact with marginal moisture return across the Mid MS/OH Valleys,
and continue into the Southeast on Monday/D6. This front is forecast
to be roughly parallel to the upper flow, and would likely undercut thunderstorms that develop along it. MUCAPE on the order of 500-1000
J/kg seems reasonable, which will support marginal severe at best.

For the latter days of the period, the forecast becomes less
predictable, however, models on a run to run basis appear to be
trending toward higher heights/possible ridging over the Southwest,
with little to no threat of severe storms.

..Jewell.. 03/18/2026

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ACUS48 KWNS 190901
SWOD48
SPC AC 190859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Thu Mar 19 2026

Valid 221200Z - 271200Z

...DISCUSSION...
On Sunday/D4, thunderstorms will be possible over parts of the OH
Valley into the Appalachians, and perhaps as far south as the TN
Valley, as an upper trough amplifies across the upper MS Valley and
into the Great Lakes. A cold front is forecast to extend
southwestward from a low over NY/PA, with perhaps lower 60s F
dewpoints and MUCAPE on the order of 500-1500 J/kg possible. Models
appear to have a wide range of instability values for Sunday, and as
such predictability is low. However, there is at least some
potential for strong to perhaps a few severe storms over the mid to
upper OH Valley. The most likely scenario is for a marginal setup
given the northwest flow pattern and modest-moisture-content warm
sector.

This front will push south toward the Gulf Coast on Monday/D5, with
high pressure building in to the north. The upper trough will move
across the Northeast on Monday, with another possibly amplifying
across the Great Lakes/Northeast Tuesday/D6 into Wednesday/D7. As
this occurs, an upper ridge is likely to exist across the Southwest,
with little overall severe potential for those days.

..Jewell.. 03/19/2026

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ACUS48 KWNS 200844
SWOD48
SPC AC 200842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Fri Mar 20 2026

Valid 231200Z - 281200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
An upper-level trough is forecast to move across the eastern U.S. on
Monday, as a cold front advances southward into the Carolinas.
Thunderstorm development will be possible in parts of the Carolinas
Monday afternoon. Instability is forecast to be weak, but a marginal
severe threat could develop in areas that heat up the most.

On Tuesday and Wednesday, northwest mid-level flow is forecast over
much of the eastern two-thirds of nation. This pattern will keep a
warm and dry airmass in place over the continental U.S., making
thunderstorms unlikely in most areas.

...Thursday/Day 7 and Friday/Day 8...
Mid-level flow is forecast to become more westerly across the
central and eastern U.S. on Thursday. In response, low-level
moisture return is forecast from the Ark-La-Tex into the mid
Mississippi Valley. Thunderstorm development will be possible from
Thursday afternoon into the overnight period across the lower to mid
Missouri Valley into the Ohio Valley, as a mid-level jet streak
passes through the north-central U.S. On Friday, a continued chance
for thunderstorm development will be possible from the mid
Mississippi Valley into the southern Appalachians. Although a severe
threat may develop on either Thursday or Friday, low predictability
exists concerning any specific scenario.

..Broyles.. 03/20/2026

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ACUS48 KWNS 210831
SWOD48
SPC AC 210829

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0329 AM CDT Sat Mar 21 2026

Valid 241200Z - 291200Z

...DISCUSSION...
...Tuesday/Day 4 to Thursday/Day 6...
An upper-level trough is forecast to move eastward into the western
Atlantic from Tuesday into Wednesday, as a surface high moves
eastward across the eastern U.S. A dry airmass is forecast across
most of the U.S., which should be unfavorable for thunderstorms in
most areas.

On Thursday, a low is forecast to develop in the northern U.S., as
low-level moisture returns quickly northward into the parts of the
Great Plains and Mississippi Valley. Thunderstorms will be possible
across this unstable airmass, mainly Thursday night, along the
southern edge of a passing mid-level jet streak. The greatest
potential for severe thunderstorms is expected from the mid
Mississippi Valley into the Ohio Valley along and near a cold front.
At this time, the amount of spread concerning potential outcomes is substantial. An area may need to be added once model solutions begin
to agree more, and confidence increases concerning where the
greatest severe threat will be.

...Friday/Day 7 and Saturday/Day 8...
On Friday, the front is forecast to move southward across the
Tennessee Valley, where isolated to scattered strong thunderstorms
will be possible during the day. The front is forecast to move
southward to near the Gulf Coast by Saturday. Isolated storms would
again be possible near the front. Although the current thinking is
that any severe threat will be marginal on Friday and Saturday,
uncertainty is substantial due to the extended range in the forecast
period.

..Broyles.. 03/21/2026

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ACUS48 KWNS 220842
SWOD48
SPC AC 220840

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0340 AM CDT Sun Mar 22 2026

Valid 251200Z - 301200Z

...DISCUSSION...
...Wednesday/Day 4 to Thursday/Day 5...
An upper-level ridge will move into the Rockies on Wednesday, as
northwesterly mid-level flow remains from the Great Plains to the
eastern U.S. On Thursday, the ridge will become less amplified as it
moves into the Great Plains. At the surface, low-level moisture is
forecast to return northward into the lower to mid Mississippi
Valley. Within this moist airmass, a pocket of moderate instability
is expected by late Thursday afternoon. Thunderstorm development
will be possible near a front along the northern edge of the
stronger instability from northeast Missouri east-northeastward into north-central Ohio. Storms are expected to move east-southeastward
across the Ohio Valley on Thursday afternoon and evening. A severe
threat will be possible, but the magnitude of any potential threat
is still uncertain.

...Friday/Day 6 and Sunday/Day 8...
From Friday into Saturday, a cold front is forecast to move
southward from the mid Mississippi Valley to the central Gulf Coast.
Isolated thunderstorms will be possible along parts of the front
both Friday and Saturday afternoon. Weak instability should keep any
severe threat marginal.

On Sunday, the models are forecasting a dry airmass over most of the continental U.S., suggesting the potential for storms is low.

..Broyles.. 03/22/2026

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ACUS48 KWNS 230900
SWOD48
SPC AC 230859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon Mar 23 2026

Valid 261200Z - 311200Z

...DISCUSSION...
...Thursday/Day 4 and Friday/Day 5...
Strong westerly mid-level flow will be in place across much of the
central and eastern U.S. on Thursday. At low-levels, moisture
advection is forecast to strengthen during the day from the mid
Mississippi Valley into the lower Ohio Valley as surface dewpoints
gradually increase into the lower to mid 60s F. A cold front is
forecast to advance southeastward into the southern Great Lakes by
Thursday afternoon, with scattered to numerous thunderstorms
developing along and near the front. Moderate instability should
develop to the south of the front, which combined with strong
deep-layer shear will likely support a severe threat during the
afternoon and evening. The greatest threat is expected to be from
northeast Missouri east-northeastward into western and northern
Ohio, where a threat area has been added for Thursday.

On Friday, a mid-level trough is forecast to dig southeastward into
the mid Mississippi Valley, as a front moves southeastward into the
Tennessee Valley and southern Appalachians. Although isolated to
scattered thunderstorms will be possible near the front during the
afternoon and evening, model forecasts suggest that instability will
remain relatively weak. This should keep any severe threat minimal.

...Saturday/Day 6 to Monday/Day 8...
The cold front is forecast to move southward through the Southeast
on Saturday and should remain near the Gulf Coast on Sunday. In its
wake, a relatively dry airmass is forecast to be in place over much
of the nation, making thunderstorm development unlikely in most
areas. On Monday, some model forecasts suggest that a mid-level
shortwave trough will move into the southern Plains. Low-level
moisture could return northward into the southern Plains Monday into
Monday night. If this where to occur, then thunderstorm activity
would be mostly likely Monday night as a low-level jet develops.
However, this scenario is highly uncertain due to the extended range
in the forecast period.

..Broyles.. 03/23/2026

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ACUS48 KWNS 240844
SWOD48
SPC AC 240842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Tue Mar 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
Widespread severe thunderstorm potential appears limited through the
remainder of March amid persistent upper-level ridging across the
central and western CONUS. Isolated to scattered thunderstorms may
materialize across portions of the TN Valley and Mid-Atlantic on
D4/Friday as a strong cold front pushes east/southeast towards the
East Coast and northern Gulf. However, limited mid-level lapse rates
across the southeastern U.S. will likely modulate the potential for
severe thunderstorms. Surface high pressure building across the
eastern Plains and OH Valley in the wake of the cold front -
combined with the re-amplification of the upper ridge over the
western U.S. - will further limit severe thunderstorm potential for
much of the weekend and very early next week.

A gradual eastward translation of the surface high will likely
promote the initial stages of moisture into the central U.S. around
the D7/Mon or D8/Tues time frame. Most deterministic solutions and
ensemble systems hint at an upper-level regime shift as the upper
ridge shifts east and southwesterly flow becomes more prominent over
the Southwest. This may support some increase in severe weather
potential by the middle of next week, and possibly as early
D8/Tuesday, but predictability at this range appears very limited.

..Moore.. 03/24/2026

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ACUS48 KWNS 250846
SWOD48
SPC AC 250844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Wed Mar 25 2026

Valid 281200Z - 021200Z

...DISCUSSION...
Severe thunderstorm potential remains limited for this weekend,
though a gradual increase in some severe threat is anticipated by
the middle of next week. In the wake of a cold frontal passage on
D3/Friday into D4/Saturday, surface high pressure building over the
eastern Plains and OH Valley will maintain dry and stable conditions
for most regions east of the Rockies. Concurrently, a slight
re-amplification of an upper-level ridge this weekend over the
Southwest/West Coast will maintain warm and dry conditions for the
southwestern CONUS. Long-range ensemble guidance continues to show a
reasonably consistent signal in the slow eastward migration of the
upper ridge through early next week. As this occurs, surface high
pressure will gradually shift off the East Coast and promote
moisture return into the Plains and MS Valley. Tight clustering of
GEFS members lends high confidence in the potential for a return of
slightly above seasonal moisture by the D6/Monday to D7/Tuesday time
frame. Thunderstorm chances should steadily increase through
mid-week as southwesterly flow aloft becomes increasingly
predominant and promotes ascent/lapse-rate advection over the
northwestern fringe of the returning moisture. Extended-range
guidance hints at severe thunderstorm potential through the
D6/Monday to D8/Wednesday time frame - mainly across the upper MS Valley/Midwest within the warm conveyor region of an organizing
cyclone. While confidence in the overall synoptic evolution through
next week is high, notable run-to-run variability in the convective
environment forecast beyond D6 suggests predictability remains too
limited to warrant highlights at this time.

..Moore.. 03/25/2026

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ACUS48 KWNS 260850
SWOD48
SPC AC 260848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Thu Mar 26 2026

Valid 291200Z - 031200Z

...DISCUSSION...
Severe weather potential will remain low through the end of the
upcoming weekend, and while a gradual increase in severe weather
potential is anticipated through next week, predictability remains
limited. Extended-range deterministic and ensemble solutions
continue to generally show good agreement in the eastward
translation of the upper ridge currently over the Southwest towards
the East Coast through the middle of next week. This will not only
result in increasing southwesterly flow over the central CONUS, but
will also promote lee troughing/cyclogenesis with an attendant
uptick in moisture return into the Plains/MS Valley.

Recent GEFS forecasts show high confidence in a return of slightly
above seasonal moisture into the eastern Plains and Midwest by the
D5/Monday to D6/Tuesday time frame. Severe thunderstorm potential is
expected to generally increase during this period as weak impulses
embedded within the broader southwest flow regime overspread the
returning moisture. Based on more bullish deterministic solutions,
some severe risk may materialize across the Midwest late D5/Monday
into D6/Tuesday within a warm frontal zone, and potentially across
the central Plains on D7/Wednesday or D8/Thursday as a cold front
pushes southeast in tandem with the intensification of a surface
low.

While these signals are noted, run-to-run variability among
deterministic guidance remains fairly high regarding the
evolution/placement of surface features and convective environments
beyond D6/Tuesday. Latest GEFS and ECENS guidance, as well as
long-range ensemble clustering and extended calibrated guidance,
show a substantial increase in variance by mid-week, which implies
limited confidence in any particular solution. While not surprising
at this range and with an upper-level regime shift yet to occur, it
remains unclear when predictability of any mid-week severe threat
will substantially improve.

..Moore.. 03/26/2026

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ACUS48 KWNS 270855
SWOD48
SPC AC 270853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Fri Mar 27 2026

Valid 301200Z - 041200Z

...DISCUSSION...
An uptick in severe thunderstorm potential is expected through the
upcoming work week and heading into next weekend. Long-range
ensemble guidance continues to show a strong signal for a return to
mean troughing across the western to central CONUS as a long-wave
ridge gradually de-amplifies and shifts east. This upper-level flow
regime will promote steady lee troughing/cyclogenesis along the High
Plains, which in conjunction with the placement of a surface high
off the East Coast, will promote moisture return northward into the
Plains and MS Valley. Strong to severe thunderstorms appear possible
multiple days next week as ascent associated with upper disturbances
embedded within the mean flow regime overspread the moisture plume.

...D4/Monday - Upper Mississippi Valley...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border during the D4/Monday to D5/Tuesday time frame. As this
occurs, surface cyclogenesis is expected across the northern Plains.
A broad swath of isentropic ascent with in the warm conveyor of the
developing cyclone will likely support showers and isolated to
scattered thunderstorms across portions of the upper MS Valley late
Monday. A few deterministic solutions, notably the recent 00z ECMWF,
hint that the convective environment will be conducive for organized convection, including the potential for elevated supercells.
However, ensemble agreement regarding this potential is limited.

...D5/Tuesday - Lake Michigan Vicinity...
Confidence is gradually increasing in a regional severe weather
threat across parts of the upper Great Lakes for D5/Tuesday. Over
the past 24 hours, model guidance has come into somewhat better
agreement regarding the timing and evolution of the northern Plains
surface low through as it translates east and intensifies across the
Great Lakes region Tuesday into early Wednesday. Above-seasonal
moisture return northward into the Great Lakes region is anticipated
by late Tuesday, which should support adequate buoyancy for deep
convection. Thunderstorm development appears likely along a trailing
cold front as it pushes southeast into the Midwest and MS Valley.
Based on ensemble guidance, the best convective environment may
reside across the Lake Michigan vicinity where mid/upper-level flow
should be stronger in vicinity to the upper jet and may be more
orthogonal to the front and supportive of more robust convection
compared to locations further south.

Despite the trend towards a more consolidated solution, notable
discrepancies remain pertaining to the propagation speed of the
upper wave and surface low, which introduces uncertainty in how
favorably timed the strongest ascent will be with peak
heating/destabilization and potential storm modes. These
uncertainties preclude probabilities at this time, but highlights
will likely be introduced as model consensus improves.

..Moore.. 03/27/2026

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ACUS48 KWNS 280858
SWOD48
SPC AC 280856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Sat Mar 28 2026

Valid 311200Z - 051200Z

...DISCUSSION...
A return to a more seasonal upper-level regime will promote
strong/severe thunderstorm chances beginning D4/Tuesday and
potentially persisting into the upcoming weekend. A well-anticipated upper-level regime shift remains likely late this weekend and into
early next week as an upper ridge over the south-central CONUS
de-amplifies and shifts east. The return to mean troughing over the
West will promote persistent lee troughing and southerly return flow
into the Plains and lower MS Valley. Long-range guidance depicts
several upper disturbances propagating across the northern and
central U.S. through late week, which may each support some risk of strong/severe thunderstorms.

...D4/Tuesday...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border and into the Great Lakes region Monday into Tuesday.
Northeastward moisture return ahead of an intensifying surface
cyclone and trailing cold front will likely establish a fairly broad
warm sector from the Ozarks into the Midwest/Great Lakes region.
Thunderstorm development along the cold front is expected by late
afternoon with most deterministic and ensemble guidance showing
strong QPF signals. Any severe weather threat will likely be focused
from central IL northeastward into northern IN/southern MI where
deep-layer wind shear will be stronger in proximity to the upper jet
and shear vectors should be more orthogonal to the front. While some
solutions depict favorable MLCAPE and shear for organized convection
(e.g. the 00z GFS), ensemble consensus shows muted probabilities for
a highly favorable convective environment (e.g. recent GEFS depicts
less than 20% probability for SCP values above 3). This suggests
that even though some severe threat will likely materialize,
considerable uncertainty remains regarding the quality of the
convective environment.

...D5/Wednesday and D6/Thursday...
Tuesday's cold front is expected to stall roughly along or south of
the OH River by the afternoon of D5/Wednesday. This will maintain a
moist warm sector across the southern Plains eastward to the TN
Valley. Strong to severe thunderstorm potential may emerge on
D5/Wednesday and D6/Thursday as an upper disturbance propagates
across the southern Plains and into the OH Valley and supports
ascent along and north of the stalled frontal zone. Given the
relatively focused nature of the wave and attendant mid-level jet,
widespread severe convection seems improbable, though a favorable buoyancy/shear environment is possible in the vicinity of the
stalled front each afternoon.

..Moore.. 03/28/2026

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