ACUS48 KWNS 220813
SWOD48
SPC AC 220812

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0312 AM CDT Tue Apr 22 2025

Valid 251200Z - 301200Z

...DISCUSSION...
...Days 4-5/Fri-Sat -- Central/Southern Plains...

An upper ridge will build over the Plains toward the MS Valley this
weekend as a deepening upper trough develops over the western U.S.
Some lead shortwave impulses will likely migrate through the ridge,
and southwesterly flow increases over the central/southern Rockies.
At the surface, persistent south/southeasterly low-level flow will
maintain a warm advection regime across the southern/central Plains,
while a daily surface dryline evolves over the High Plains. While
some severe potential may occur Friday and Saturday over parts the central/southern Plains, uncertainty remains quite high given
several periods of convection leading into Friday, as well as
ongoing convection Friday morning, and possible capping concerns
beneath the upper ridge both days. This precludes 15 percent
probability delineation at this time, but probabilities may be
needed in subsequent outlooks as smaller scale details become better
resolved.

...Days 6-8/Sun-Tue -- Great Plains to the Upper Midwest...

A more active severe weather period is possible early next week as
the western U.S. trough develops eastward into the Plains and Great
Lakes vicinity. The upper trough may begin ejecting into the
southern/central Plains as early as Day 6/Sun. However, the timing
of this feature may be ill-timed with peak diurnal
heating/destabilization such that stronger large-scale ascent and
increasing southwesterly flow aloft arrive overnight. Forecast
soundings Sunday afternoon suggest capping may limit convection.

By Day 7/Mon, a strong midlevel jet streak should overspread
portions of the central/southern Plains into the Upper Midwest. Lee cyclogenesis is forecast across the central High Plains, resulting
in a sharpening dryline across portions of the Great Plains, and
warm front extending across the eastern Dakotas to the Mid-MS
Valley. Rich Gulf moisture will be in place across the warm sector
and widely scattered severe storms appear possible from Monday
afternoon into Monday night. As is typical at longer time frames,
forecast guidance differs in exact timing and placement of key
features. However, the overall pattern is favorable for an
all-hazards severe weather episode, and a 15 percent delineation has
been included, though this area may shift over the coming days as
details become better resolved.

Severe potential may continue into Day 8/Tue across portions of the
Midwest to the southern Plains as a shortwave upper trough continues
across the Great Lakes into southeast Canada, and a cold front
impinges southeastward over portions of the region. Uncertainty
increases considerably during this time, precluding 15 percent
probabilities at this time.

..Leitman.. 04/22/2025

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ACUS48 KWNS 030824
SWOD48
SPC AC 030822

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CDT Thu Apr 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
Models are in relatively good agreement for the Sunday/D4 to
Monday/D5 period, depicting an elongating upper trough sweeping east
from the OH/TN Valleys to the East Coast.

On Sunday/D4, a leading midlevel wave is forecast to move out of AR
and across TN/KY, with little amplitude and poor lapse rates by this
time. An extensive area of rain and thunderstorms will be ongoing
along the length of the cold front throughout the day, from the
Northeast to the northern Gulf Coast. Some severe wind threat is
expected, mainly over parts of the Southeast where dewpoints will be
higher and as deep-layer shear remains favorable.

The trend of widespread precipitation along this front will continue
into early Monday/D5, from the Carolinas into FL. The severe risk
should continue to dwindle as large-scale support weakens, but
low-end potential cannot be ruled out over these areas.

For the Tuesday/D6 to Thursday/D8 time frame, the weather pattern
will be much less conducive to severe storms, with a ridge building
over the West, and northwest flow across the central states.
Periodic surges of high pressure are forecast, helping to keep
conditions mostly stable over the bulk of the CONUS.

..Jewell.. 04/03/2025

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ACUS48 KWNS 120843
SWOD48
SPC AC 120841

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CDT Sat Apr 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
After a relative lull in severe potential mid-week, latest guidance
indicates increasing severe possibilities late week. Compared to 24
hours ago, deterministic models have vastly changed to an evolution
of a shortwave trough digging south from the Canadian Rockies into
the Lower CO Valley during D5-7/Wednesday-Friday. This would support
a greater breadth and quality of western Gulf moisture advection
across the central states beneath an initially pronounced EML. SPC
and NSSL GEFS-based ML guidance indicate broadening 5 to mesoscale
pockets of 15 percent probabilities during D6-8/Thursday-Saturday.
But given the lack of day-to-day continuity and rather large spread
across ensemble guidance, consideration of any severe area appears
premature this cycle.

..Grams.. 04/12/2025

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ACUS48 KWNS 150900
SWOD48
SPC AC 150858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Tue Apr 15 2025

Valid 181200Z - 231200Z

...DISCUSSION...
An active severe weather pattern expected through at least this
weekend, before predictability diminishes early next week.

...D4/Friday...
Guidance remains consistent with a broad swath of strong mid-level southwesterlies from the southern High Plains to the Great Lakes,
downstream of a longwave trough from northern ON to the Lower CO
Valley. This will overlap a similarly oriented surface front. In
response to increasing mid-level height falls, a surface cyclone
should track across the central Great Lakes portion of the
baroclinic zone during the day. Afternoon severe may be focused in
this region with stronger low-level shear. Parts of this region may
warrant higher probabilities in later outlooks.

Farther southwest, a pronounced EML may delay the bulk of storm
development along the front until evening. But given the strong
deep-layer shear and moderate buoyancy, scattered severe storms
appear possible.

...D5/Saturday...
Amplification of an embedded northern-stream shortwave impulse over
ON/QC should sustain an expansive swath of strong mid-level flow
from the OH Valley northeastward. The northeast extent of
appreciable instability overlapping with this regime becomes
nebulous east of the Appalachians, but scattered severe storms seem
possible from the Cumberland Plateau into the Mid-South on Saturday
afternoon to evening.

Over the southern Great Plains, lingering convection Saturday
morning renders uncertainty along the largely stalling baroclinic
zone that will undoubtedly be modified by convective outflow. But
with greater consistency in guidance handling the pivot of the basal
shortwave impulse across the Southwest, multiple rounds of strong to
severe convection are plausible through Saturday night.

...D6/Sunday...
Predictability lessens by this period with the evolution of compact
shortwave trough ejecting onto the southern Great Plains. This
yields substantial spread in the attendant synoptic cyclone. In
addition, potentially extensive ongoing convection Sunday morning
further lessens confidence in mesoscale details. But a belt of
potentially very strong mid-level southwesterlies overlapping rich
western Gulf moisture supports inclusion of a severe-area highlight
in the South-Central States.

..Grams.. 04/15/2025

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ACUS48 KWNS 100834
SWOD48
SPC AC 100833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Apr 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Primary feature of interest will be a shortwave trough over MT at
12Z Sunday and its major amplification into a broad eastern
CONUS/southeast Canadian trough through mid-week. Poleward moisture
quality from the western Gulf will remain sub-optimal, but will
improve through D5/Monday. The northeast extent of weak surface
buoyancy should reach the OH Valley by Monday afternoon, where
guidance has been trending farther south with an intense mid-level
jet. Given a prior EML and the deep surface cyclone tracking over
Lake Superior to central ON vicinity, convective coverage may be
limited along the trailing cold front. Still, consensus of guidance
suggests that some fast-moving convection should accompany the
portion of the front in the OH Valley vicinity. Robust 700-500 mb
wind profiles should offer at least a threat for damaging winds.

Depending upon timing of frontal passage, a limited-area severe
threat may exist on D6/Tuesday along the Southeast Atlantic coast. A
compact southern-stream shortwave impulse, approaching the backside
of the broad east CONUS trough, indicates low-probability severe
potential over the southern Great Plains on D7/Wednesday into the
western Gulf Coast vicinity D8/Thursday.

..Grams.. 04/10/2025

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ACUS48 KWNS 110832
SWOD48
SPC AC 110830

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CDT Fri Apr 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
...D4/Monday...
Further amplification of a broadening mid/upper-level trough and
attendant surface cyclone is expected across the Upper Great Lakes
to the southern ON/QC border area. Poleward moisture quality from
the western Gulf will remain sub-optimal, but will continue to
improve beneath a lobe of the southern Great Plains EML. The
northeast extent of weak surface buoyancy should overspread the OH
Valley by Monday afternoon. This portion of the front will coincide
with robust 700-500 mb southwesterlies, yielding potential for
fast-moving convection. Guidance consensus suggests this will remain
the favored corridor for at least a damaging wind threat.

...D7/Thursday...
Guidance has trended towards greater amplification of a Prairie
Provinces to north-central CONUS upper trough, although run-to-run
continuity is quite poor. This would be accompanied by a cold front
sweeping southeast into the South-Central States. With potentially
greater low-level moisture relative to the D3-4 system, some severe
potential may become evident once predictability improves.

..Grams.. 04/11/2025

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ACUS48 KWNS 130853
SWOD48
SPC AC 130851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Sun Apr 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
An active severe weather pattern is expected late week into next
weekend.

...D5/Thursday...
Guidance has converged to a signal of severe-storm threat centered
on Thursday evening as a deep surface cyclone becomes established in
the KS vicinity, downstream of a longwave trough in the West. An
enriching low-level moisture plume will be advected nearly due north
from the western Gulf towards the Lower MO Valley. A stout EML
should limit convective development along much of the dryline. But a strengthening low-level jet should support thunderstorm development
to the northeast of the surface low amid strong deep-layer shear.

...D6/Friday...
A rather broad swath of 50+ kt 500-mb southwesterlies appears likely
to become established from the southern High Plains to the Great
Lakes, downstream of a broad trough in the Southwest and a separate northern-stream wave around northern ON. While the deep cyclone over
the KS vicinity will weaken, it should track towards the central
Great Lakes in response to the northern wave. Along its trailing
cold front, extensive thunderstorm development is anticipated Friday afternoon/evening. Given the aforementioned strong mid-level flow
regime, a broad corridor of severe threat is warranted.

...D7-8/Saturday-Sunday...
Predictability for a 15 percent highlight wanes somewhat next
weekend, but areas will probably be needed in later outlooks.
Saturday may consist of confined, bimodal threat areas across the
Lower Mid-Atlantic States and southern High/Great Plains. For the
former, the degree of instability and position of a southeast-moving
cold front on the periphery of a fast zonal flow regime are the main uncertainty drivers. For the latter, timing of the pivot and
eastward ejection of the Lower CO Valley shortwave impulse into the south-central states will be critical. Based on latest guidance, it
appears Sunday could have a broader corridor of severe potential.

..Grams.. 04/13/2025

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ACUS48 KWNS 140852
SWOD48
SPC AC 140850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Mon Apr 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
Active severe weather pattern expected late week into the weekend.

...D4/Thursday...
A longwave trough should become clearly anchored over the West and
consist of multiple embedded shortwave impulses. Peak surface
cyclone amplitude is largely progged over western KS on Thursday
afternoon, with a dryline arcing across eastern KS into the southern
Great Plains. Another day of modifying moisture return northward
from the western Gulf should yield at least moderate buoyancy ahead
of the dryline. A strengthening low-level jet should support
thunderstorm development across the Lower MO to Mid-MS Valleys on
Thursday evening. Supercell wind profiles support potentially
scattered severe storms.

...D5/Friday...
A broad swath of strong mid-level southwesterlies appears likely
to become established from the southern High Plains to the Great
Lakes, downstream of a longwave trough from James Bay to the Lower
CO Valley. While the deep cyclone over the KS vicinity will weaken,
it should move towards the central Great Lakes. From along/ahead of
its track to the trailing cold front arcing southwestward into west
TX, extensive thunderstorm development is anticipated Friday
afternoon/evening. Given the strong mid-level flow regime, scattered
severe storms are possible across an elongated corridor.

...D6-7/Saturday-Sunday...
Predictability for a 15 percent highlight remains too low during the
weekend, but areas will probably be needed in later outlooks.
Guidance has trended neutral to slightly weaker/more confined
potential on Saturday. Overall signal persists of bimodal primary
threat areas across the Lower Mid-Atlantic States and southern
High/Great Plains. For the former, the degree of instability and
position of a southeast-moving cold front on the periphery of
stronger zonal mid-level flow remain key uncertainty factors. For
the latter, timing of the pivot and eastward ejection of the compact
Lower CO Valley shortwave impulse across the Southwest/southern
Rockies remains crucial. Guidance has shown poor run-to-run
continuity for Sunday, yielding low confidence on spatial details of
the severe threat. Across both regimes and days, NSSL GEFS ML sub-15
percent probabilities appear quite reasonable.

..Grams.. 04/14/2025

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ACUS48 KWNS 180736
SWOD48
SPC AC 180734

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CDT Fri Apr 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
An upper shortwave trough will weaken as it spreads east/northeast
from the Mid/Upper MS Valley to the Lower Great Lakes on Day 4/Mon.
The associated surface low will likewise shift northeast from
eastern IA/IL into Ontario, while a trailing cold front moves across
much of the Midwest. Modest boundary-layer moisture will aid in weak destabilization and some low-end severe thunderstorm risk could
develop across parts of the Ohio Valley/Lower Great Lakes vicinity.
The southern extent of this front will stall across the Mid-South
and Sabine Valley. Richer low-level moisture ahead of the surface
boundary across parts of the South could support some thunderstorm
risk as well, but nebulous forcing and weak vertical shear will
limit severe potential.

On Days 5-8/Tue-Fri, a low-amplitude, weak flow pattern is forecast.
Southerly low-level flow across the Gulf and southern Plains will
allow for northward moisture transport across OK/TX and vicinity.
Diurnal thunderstorm activity could be possible each day given
modest west/southwest flow atop a moist warm sector. However, a
rather nondescript surface pattern amid weak large-scale forcing
will likely preclude widespread severe potential, though localized
areas of severe storms could still occur given favorable
moisture/instability, particularly along any dryline features.

..Leitman.. 04/18/2025

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ACUS48 KWNS 190753
SWOD48
SPC AC 190752

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 AM CDT Sat Apr 19 2025

Valid 221200Z - 271200Z

...DISCUSSION...
...Days 4-6/Tue-Thu -- Southern Plains...

A low-amplitude west/southwesterly mid/upper flow pattern will
prevail Days 4-6/Tue-Thu. South/southeasterly low-level flow across
the western Gulf into the southern Plains will allow for northward
moisture transport and daily diurnal destabilization. In the absence
of any stronger shortwave troughs moving through the weak
west/southwesterly flow regime, severe potential is uncertain and
will likely be driven by mesoscale/local processes, precluding 15
percent probabilities at this time.

..Leitman.. 04/19/2025

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ACUS48 KWNS 040823
SWOD48
SPC AC 040822

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0322 AM CDT Fri Apr 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
...Monday/Day 4 and Tuesday/Day 5...
On Monday, a cold front is forecast to move southeastward across the
eastern Carolinas, southeast Georgia and Florida. It appears that
pockets of moderate instability will be possible ahead of the front
by midday. Considering that strong deep-layer shear is forecast
across much of the Southeast, thunderstorms that form near the front
could develop an isolated severe threat. Severe wind gusts would be
possible near the leading edge of a convective line. However, the
timing of the cold front as it passes through the Southeast remains questionable, and uncertainty exists concerning instability,
suggesting predictability is low for Monday.

On Tuesday, surface high pressure is forecast to move across the
central and eastern U.S. Relatively dry and stable air should limit
any severe potential across the continental U.S Tuesday.

...Wednesday/Day 6 to Friday/Day 8...
From Wednesday to Friday, a cold front and an associated mid-level
trough is forecast to move southeastward across the central and
eastern U.S. Thunderstorm development will be possible ahead of the
trough near the front, beginning Wednesday night in the central
Plains. The most reliable model forecasts suggest that the most
likely area for an isolated severe threat on Thursday would be from
the central Plains into the mid Mississippi Valley. The severe
potential is forecast to shift eastward into the Carolinas on
Friday. Severe wind gusts and hail would be the primary threats.
During the mid to late week, instability is forecast to remain
relatively weak ahead of the front. Also, the timing of the trough
is still in question. This suggest that predictability is low from
Wednesday to Friday.

..Broyles.. 04/04/2025

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ACUS48 KWNS 050849
SWOD48
SPC AC 050848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sat Apr 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
A mid-level trough is forecast to move across the Atlantic Coastal
states on Tuesday, as a dry airmass moves across the eastern and
southern U.S. From Wednesday to Friday, a mid-level trough is
forecast move southeastward from the central states into the eastern
U.S., becoming increasingly amplified with time. Ahead of this
feature, instability is forecast to remain weak. Isolated severe
storms would be possible ahead of the trough in the lower Missouri
and mid Mississippi Valleys Wednesday night. The severe threat is
forecast to shift eastward into the Ohio and Tennessee Valleys on
Thursday, and to the Carolinas on Friday. One of these days could be
a potentially more active severe weather day, but predictability
remains low concerning trough timing, magnitude of instability and
convective mode. In the Great Plains from Friday into Saturday,
model forecasts suggest a moist airmass will advect northward across
the southern and central Plains. At mid-levels, a ridge is forecast
to move eastward across the central U.S. from Friday into Saturday.
Isolated severe storms that develop in the vicinity of the ridge
should be marginalized due to a lack of large-scale ascent.

..Broyles.. 04/05/2025

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ACUS48 KWNS 070859
SWOD48
SPC AC 070857

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Mon Apr 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
...Days 4-5/Thursday-Friday...
A positively tilted large-scale trough will move slowly
east-southeastward across the Mid MS and OH Valleys on Day
4/Thursday. Ahead of the trough, partially modified Gulf moisture
will be returning ahead of a related front moving across the Lower
MS Valley. Thunderstorms are expected ahead of the front across
parts of the OH/TN Valleys, where weak buoyancy and strong midlevel
westerly flow will support an isolated severe-storm risk. However,
the limited low-level moisture and weak/veered low-level flow should
limit storm intensity. By Day 5/Friday, the midlevel trough will
take on a neutral tilt as it moves slowly eastward and amplifies
across the Appalachians. Preceding the trough, strong
south-southwesterly midlevel flow will overspread the partially
modified Gulf air mass over the coastal Mid-Atlantic -- where
isolated severe storms will be possible ahead of a related surface
front. Similar to Day 4/Thursday, the overall threat appears too
marginal for severe probabilities at this time.

...Days 7-8/Sunday-Monday...
A midlevel trough and strong west-southwesterly flow will overspread
the northern/central Plains on Day 7/Sunday, and continue across the Midwest/Great Lakes on Day 8/Monday. In response, boundary-layer
moisture will return northward ahead of a related lee trough across
the southern and central Plains on Day 7/Sunday, though a strong EML
should limit thunderstorm potential. By Day 8/Monday, guidance
varies considerably on the evolution of the midlevel trough and
related warm sector, limiting confidence in overall severe-storm
potential.

..Weinman.. 04/07/2025

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ACUS48 KWNS 200825
SWOD48
SPC AC 200823

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0323 AM CDT Sun Apr 20 2025

Valid 231200Z - 281200Z

...DISCUSSION...
A low-amplitude southwesterly flow regime will prevail for much of
the Day 4-8 period across portions of the central and eastern U.S.,
with a mean upper trough persisting across the western states.
Persistent south/southeasterly low-level flow across the Gulf and
southern Plains will result in northward transport of rich
boundary-layer moisture across the southern and parts of the central
Plains through at least Day 6/Fri. Forecast guidance suggests weak
shortwave impulses may float through modest southwesterly flow Days 4-5/Wed-Thu, perhaps providing some support for isolated to
scattered thunderstorm potential across the warm sector over
TX/OK/KS. Given a moist and unstable airmass, at least some severe
potential will exist. However, where exactly severe potential may
develop Day 4-5/Wed-Thu is uncertain given a lack of stronger
large-scale ascent and absence of any substantial surface
cyclogenesis, coupled with modest deep-layer flow. This precludes 15
percent probabilities at this time, though outlook areas could
become necessary in later outlooks as smaller-scale features become
better resolved.

A period of weak upper ridging may spread across the Plains and the
eastern U.S. on Days 6-7/Fri-Sat ahead of a more substantial upper
trough developing over the western U.S. This may limit severe
potential late in the week before the western upper trough ejects
east toward the end of the forecast period.

..Leitman.. 04/20/2025

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ACUS48 KWNS 210809
SWOD48
SPC AC 210807

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0307 AM CDT Mon Apr 21 2025

Valid 241200Z - 291200Z

...DISCUSSION...
...Day 4/Thu -- Central/Southern Plains...

Some severe thunderstorm potential is possible across the
southern/central Plains on Day 4/Thu. Similar to the Day 2-3/Tue-Wed
period, a low-amplitude, and generally modest deep-layer
southwesterly flow regime will persist. Southerly low level flow
ahead of a southward sagging front across the central Plains, and to
the east of a dryline extending southward across the southern High
Plains will sustain advection of Gulf moisture across the region. At
least some risk for isolated severe thunderstorms appears possible
within the moist/unstable warm sector. However, convection may be
ongoing across portions of the region Thursday morning, and given a
lack of any stronger upper forcing regime or surface cyclogenesis,
confidence in where greater severe potential may develop is low,
precluding 15 percent delineation at this time.

...Days 5-6/Fri-Sat -- Southern Plains vicinity...

Upper riding is forecast to overspread the Plains late in the week
ahead of a deepening western U.S. upper trough. A cold front will
sag south and east on Friday, extending from the Ohio Valley into
the southern High Plains. As the upper ridge builds, richer Gulf
moisture will develop across TX into OK. Some localized
strong/severe storms may develop across west TX during this time
within the moist upslope flow regime, but the upper ridge and weak
forcing should suppress more widespread severe potential.

...Days 7-8/Sun-Mon -- Plains to the MS Valley...

Severe potential is likely to increase from OK/TX into the central Plains/Mid-MO Valley by early next week as the western upper trough
begins to eject eastward. This should result in stronger
southwesterly mid/upper flow overspreading a broad warm sector. This
overall pattern is a synoptically favorable spring time pattern for
severe storms across the Plains. Furthermore, control members and
ensemble members from the GFS and ECMWF are in fairly good agreement
regarding the timing/location of the ejecting upper trough and
stronger southwesterly flow overspreading the region. Nevertheless,
uncertainty remains too high to include 15 percent delineated areas
at this time. This is particularly the case of Day 7/Sun where
forecast guidance has widespread precipitation ongoing during the
morning. Given the otherwise favorable pattern, severe probabilities
will likely be needed in the coming days as details become better
refined.

..Leitman.. 04/21/2025

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ACUS48 KWNS 060853
SWOD48
SPC AC 060852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CDT Sun Apr 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
...Wednesday/Day 4 to Friday/Day 6...
During the mid to late week, a mid-level shortwave trough is
forecast to amplify and move southeastward from the north-central
states into the eastern U.S. Low-level moisture return ahead of the
trough is expected to be slow, which should result in only weak
instability ahead of the system. As the trough progresses
southeastward, isolated strong thunderstorms will be possible
Wednesday night in parts of the central Plains. On Thursday, an
isolated severe threat may develop in parts of the Ozarks and
Ark-La-Tex. By Friday, the system is forecast to be in the
Southeast, where isolated severe storms will be possible in parts of
Georgia and the Carolinas. Any severe threat that develops from
Wednesday to Friday is expected to be marginal, mainly due to issues
with poor moisture return and relatively weak instability.

...Saturday/Day 7 and Sunday/Day 8...
On Saturday, a mid-level ridge is forecast to move eastward across
the central U.S. Some low-level moisture is expected to return
northward into the Great Plains, where instability may become strong
enough for a severe threat. However, subsidence in the vicinity of
the ridge is expected to keep any threat that develops very
isolated.

On Sunday, model forecasts suggest that a long fetch of
west-northwest mid-level flow becomes established over much of the
U.S. Although isolated thunderstorms may form within a somewhat
moist airmass over parts of the south-central states Sunday
afternoon, large-scale ascent is forecast to remain weak. This,
combined with uncertainties at this extended range, suggest that
predictability is low.

..Broyles.. 04/06/2025

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ACUS48 KWNS 080839
SWOD48
SPC AC 080837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Tue Apr 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
On Day 4/Friday, an amplified large-scale trough will move slowly
eastward across the Appalachians. Ahead of a related surface low in
the lee of the Appalachians, weakly modified boundary-layer moisture
will be in place across the coastal Mid-Atlantic states. While
instability will be marginal, owing to the limited moisture and poor
lapse rates, strong south-southwesterly midlevel flow may support a
couple strong storms during the afternoon. The overall severe threat
appears too marginal for severe probabilities at this time.

By Day 6/Sunday, a midlevel trough will advance eastward across the northern/central Plains, while an elongated downstream surface
trough (with embedded surface lows) promotes partially modified Gulf
moisture return across the southern/central Plains and MS Valley.
Despite multiple surface boundaries across the Plains, current
indications are that a strong EML and related capping atop the
limited boundary-layer moisture should inhibit surface-based
thunderstorm potential.

Thereafter, medium-range guidance varies considerably regarding the
timing and evolution of the aforementioned midlevel trough and
associated warm sector -- limiting confidence in severe-storm
potential for Days 7-8/Monday-Tuesday.

..Weinman.. 04/08/2025

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ACUS48 KWNS 090839
SWOD48
SPC AC 090837

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0337 AM CDT Wed Apr 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
From Day 5/Sunday through Day 6/Monday, a robust midlevel trough
will advance eastward from the northern Plains to the Great Lakes.
On Day 5/Sunday, a related broad/elongated surface low will move
eastward across the northern/central Plains, while a dryline
develops farther south over the southern Plains. Isolated strong
storms may be possible ahead of the surface low in the Upper MS
Valley, though poor boundary-layer moisture will tend to limit the
severe risk. Farther south along the dryline, a strong EML and
related capping should inhibit thunderstorm development, despite the development of larger buoyancy here.

On Day 6/Monday, a cold front will move across the eastern half of
the CONUS, in tandem with the eastward-moving trough. Strong
midlevel flow and a weakly unstable air mass along the front may
support a marginal severe-storm risk from the OH Valley
southwestward to the Ozarks. However, considerable differences among
the medium-range guidance regarding the quality of boundary-layer
moisture ahead of the front casts uncertainty on the overall risk.

..Weinman.. 04/09/2025

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ACUS48 KWNS 160853
SWOD48
SPC AC 160851

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0351 AM CDT Wed Apr 16 2025

Valid 191200Z - 241200Z

...DISCUSSION...
Severe potential remains apparent into the weekend, but
predictability wanes substantially by D5/Sunday.

...D4/Saturday...
The persistent longwave trough is expected to breakdown as an
embedded northern-stream shortwave impulse accelerates east across
ON/QC and the basal shortwave impulse moves more gradually east into
the southern High Plains. Through Saturday afternoon, an expansive
swath of strong mid-level flow will persist from the central
Appalachians southwestward into the southern Great Plains. The
nearly stalled baroclinic zone from TX/OK into the Lower OH Valley
will likely be modulated by ongoing convection on Saturday morning.
But with appreciable boundary-layer heating of a seasonably moist
air mass to the south-southeast, scattered severe storms are
plausible from the Upper OH Valley through central TX.

...D5/Sunday...
The 00Z GFS and related GEFS are substantially different relative to
24 hours ago with the evolution of the compact shortwave trough
ejecting across the southern Great Plains and the attendant synoptic
cyclone. Most other guidance has remained relatively consistent to
prior days with probable cyclogenesis from OK to the Lower MO
Valley. This would result in a confined belt of strong mid-level southwesterlies overlapping a broad warm sector with rich western
Gulf moisture. Potentially extensive convection in parts of OK/TX on
Sunday morning does complicate exactly how far north-northwest
appreciable destabilization may occur into the Ozarks/Lower MO
Valley and beyond. Overall setup outside of the GFS-based guidance
appears to support scattered severe storms across the South-Central
States on Sunday afternoon/evening.

..Grams.. 04/16/2025

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ACUS48 KWNS 170831
SWOD48
SPC AC 170830

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CDT Thu Apr 17 2025

Valid 201200Z - 251200Z

...DISCUSSION...
...Day 4/Sun - ArkLaTex to the Mid-MS Valley...

A compact upper shortwave trough is forecast to move from the
southern High Plains to the Midwest on Sunday. While some forecast
uncertainty continues with regard to exact position of this feature,
the overall pattern suggests isolated to scattered severe
thunderstorm potential will exist across portions of east TX into
the Mid/Lower MS Valley.

Strong southwesterly flow aloft will overspread a moist warm sector
as a surface low lifts north/northeast from OK into the Lower MO
Valley through early evening. A trailing cold front will spread east
as this occurs, while a warm front extends eastward from the Mid-MS
Valley into the OH Valley. Evolution of prior days convection is
resulting in some uncertainty regarding the western/northern extent
of severe potential. Nevertheless, a favorable environment
supporting at least isolated severe storms should extend from east
TX into parts of southern MO/IL ahead of the cold front.

...Days 5-8/Mon-Thu...

Forecast ensemble guidance from both the GEFS and EPS suggest
low-amplitude west/southwesterly flow will overspread the southern
tier of the U.S. next week. Southerly low-level flow on Day 5/Mon
across the western Gulf into the southern Plains in the wake of the
cold frontal passage on Day 4/Sun will allow for northward transport
of modified moisture. This should continue into Day 6/Tue across the
Plains. Some localized severe risk could develop across parts of the
southern Plains as an upper shortwave trough moves across the
north-central U.S. on Day 6/Tue, but poor juxtaposition between
higher quality moisture across OK/TX and stronger forcing across the
northern Plains/Upper Midwest may limit overall potential. This
low-amplitude pattern will continue through Day 8, resulting in low predictability.

..Leitman.. 04/17/2025

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ACUS48 KWNS 230817
SWOD48
SPC AC 230815

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0315 AM CDT Wed Apr 23 2025

Valid 261200Z - 011200Z

...DISCUSSION...
...Days 5-7/Sun-Tue -- Great Plains to the Midwest...

Forecast guidance is in good agreement that a deepening upper trough
over the western states will eject eastward across the Plains and
Midwest early next week. Beginning Day 5/Sun, the upper trough will
extend from the central Rockies to the Southwest, with a belt of
strong southeasterly flow emerging over the central/southern High
Plains Sunday night. Surface lee low development is forecast over
the northern/central Plains Sunday afternoon, with the low moving
into SD/NE by Monday morning. Southerly low-level flow will
transport ample moisture northward across the Plains and Mid-MO
Valley on Sunday, with a sharpening dryline extending southward from
western NE into western TX. Some severe potential could develop
along the dryline and near the surface low/triple point. However,
forecast soundings maintain strong capping and any convective
development could be rather sparse. For now, this will preclude
severe probabilities for Day 5/Sun.

On Day 6/Mon, the upper trough will continue eastward, moving into
the Plains by Tuesday morning. Ahead of the trough, a belt of strong southwesterly flow aloft will extend from OK into the Upper Midwest.
A deepening surface low over SD will shift east/northeast through
the period, with a trailing cold front shifting east/southeast
across the Plains. Rich boundary layer moisture within a moderate to
strongly unstable airmass and favorable shear parameter space will
support an all-hazards severe weather episode across a fairly broad
area from OK to MN/WI Monday afternoon into Monday night.

Severe potential is likely to continue into Day 7/Tue, though some
differences within medium range guidance with the evolution of the
upper trough and key surface features does result in a bit more
uncertainty compared to Monday, especially on the eastward extent of
severe potential. Nevertheless, strong forcing atop a broad warm
sector ahead of an eastward advancing cold front will continue to
support severe potential from northeast Texas into Lower MI.

..Leitman.. 04/23/2025

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ACUS48 KWNS 240848
SWOD48
SPC AC 240847

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0347 AM CDT Thu Apr 24 2025

Valid 271200Z - 021200Z

...DISCUSSION...
...Day 4/Sun - Great Plains...

An upper trough over the southwestern U.S. early Sunday will develop
east, becoming oriented from the central Rockies to the Lower CO
Valley by Monday morning. As the trough develops east, a band of
enhanced southwesterly mid/upper flow will overspread NM northeast
to the Dakotas. A lee surface cyclone will deepen over western
SD/NE, eventually shifting east into eastern SD by early Monday.
Southerly low-level flow will transport Gulf moisture northward
across the Plains as a dryline sharpens over western portions of the
Plains. An EML should limit diurnal thunderstorm activity, though an
isolated supercell can not be ruled out somewhere along the dryline
from western SD southward into west TX. As a 50-60 kt low-level jet
develops overnight, elevated convection may develop near the surface
low over parts of SD/ND. This activity could pose a risk for hail,
but uncertainty precludes 15 percent probabilities at this time.

...Day 5/Mon - Southern Plains to Upper Midwest...

A shortwave trough embedded within the larger-scale western U.S.
upper trough will eject from the central Rockies to the Upper
Midwest on Monday. The southern branch of the western upper trough
will stall over the Four Corners vicinity, but a broad swath of
50-80 kt 500 mb southwesterly flow will extend from the southern
Plains to the upper Great Lakes. A surface low will shift east
across the Upper MS Valley, with a trailing cold front moving across
the northern/central Plains into WI/IA during the afternoon and
overnight hours. A dryline also will extend southwest from
northeast/central KS into western OK/northwest TX.

Rich Gulf moisture will be transported northward on increasing
southerly low-level flow ahead of the aforementioned surface
features. Moderate to strong destabilization is forecast from OK
northeast into IA and adjacent parts of southern MN/southwest WI.
Supercell wind profiles amid this very moist/unstable airmass will
support an all-hazards severe risk. The greatest risk should be
centered on IA and adjacent areas from extreme northeast KS into
southeast MN/southwest WI, where an intense low-level jet is
expected to develop by late afternoon/early evening.

With southwest extent across eastern KS into OK, and northwest TX,
convective coverage is less certain as capping my limit severe
thunderstorm development. Current model trends hanging back the
southern branch of the upper trough also suggests large-scale ascent
will be weaker across the region, resulting in a more difficult time
overcoming capping. Higher probabilities may be needed in subsequent
outlooks if trends suggest capping will be less of a hindrance.

...Day 6/Tue - North TX into southern Lower MI and OH...

Severe potential will continue into Tuesday, especially from the
Mid-MS Valley into Lower MI/OH where the surface cold front is
expected to continue pushing east/southeast through the period.
While the upper shortwave trough over the Great Lakes will deamplify
through the day, enhanced southwesterly flow atop the frontal
boundary and a moist/unstable airmass should continue to support
severe thunderstorm organization in the form of clusters and line
segments.

With southwest extent into AR/eastern OK/north TX, large-scale
ascent will become weaker. However, persistent warm advection in the
vicinity of a stalled boundary, and potential secondary surface low
development should foster strong/severe thunderstorm activity.

...Days 7-8/Wed-Thu... OK/TX into the Lower MS Valley...

Forecast guidance shows the southwestern U.S. upper trough ejecting
across the southern Plains and Lower MS Valley by the end of the
forecast period. This could bring severe thunderstorm potential to
these regions (OK/TX on Wed, ArkLaTex/Lower MS Valley on Thu).
However, several periods of thunderstorm activity leading into
Wednesday and large surface pattern differences among medium range
guidance precludes introduction of severe probabilities at this
time.

..Leitman.. 04/24/2025

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ACUS48 KWNS 250856
SWOD48
SPC AC 250854

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Fri Apr 25 2025

Valid 281200Z - 031200Z

...DISCUSSION...
...Day 4/Mon - Southern Plains to Upper Midwest...
A strong mid-level jet streak will move rapidly northeastward from
the Southwest to the Upper Midwest on Monday. As this occurs, a
surface low will deepen and move from the northern Plains to the
northern Great Lakes. Strong southwesterly lower tropospheric flow
will advect high theta-e air northward across the Midwest and into
parts of the Upper Midwest. Broken to scattered cloudcover will
support surface heating and strong destabilization across the warm
sector from southeast Minnesota and western Wisconsin to the
southern Plains. Isolated to scattered supercells are likely along
the dryline which will extend from the southern Plains and into
Kansas.

The greatest focus for severe weather on Monday will be from eastern
Kansas into northern Missouri, much of Iowa and into southern
Minnesota and western Wisconsin. Moderate to strong instability,
strong shear, and increasing forcing for ascent supports the
potential for numerous rounds of severe thunderstorms. The wind
profile supports supercells capable of all severe weather hazards
including the potential for strong tornadoes.

...Day 5/Tue - Southern Plains to parts of the Northeast...
The surface low associated with the Day 4 threat will continue
northeast and bring its associated cold front eastward across the
Midwest and Great Lakes through the day Tuesday. Moderate to strong
instability is forecast south of this front from northern New York
to the Ohio Valley. Much of the frontal zone should have sufficient
shear to support multiple storm clusters and the potential for a few supercells.

Day 6/Wed-Day8/Fri - Portions of the Mid-Mississippi Valley into the Southeast...
A weaker mid-level shortwave trough is consistently depicted by
extended range guidance by the middle of next week across the
southern Plains. However, significant uncertainty remains about the
strength of this trough and location of any frontal zones. In
addition, convection across the southern Plains each day of the
extended range forecast could significantly impact destabilization
by Day 6-8. Therefore, confidence is not high enough to add
probabilities at this time, but they may eventually be needed
somewhere across the Southeast/Mid Mississippi Valley.

..Bentley.. 04/25/2025

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ACUS48 KWNS 260849
SWOD48
SPC AC 260848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sat Apr 26 2025

Valid 291200Z - 041200Z

...DISCUSSION...
...Day 4/Tuesday - West Texas to the Northeast...
Moderate instability will be present along an elongated frontal zone
from the southern Plains to the Northeast on Tuesday. Modest shear
along the frontal zone will support some organization into multicell
clusters and perhaps supercells. A greater severe weather threat
will exist across the eastern Great Lakes where forcing and shear
will be strongest as a 75 knot mid-level jet streak crosses southern
Ontario.

Another focused zone of greater coverage of severe storms will be
across parts of West Texas where multiple rounds of storm are
anticipated. The first chance of storms will be during the afternoon
as the front continues to move south across Oklahoma and perhaps
into North Texas. An additional round of storms will be possible
across parts of West Texas as the low-level jet strengthens Tuesday
night in the presence of strong instability and shear.

...Day 5/Wednesday - North Texas to the ArkLaTex...
Ongoing Day 4 convection may have some impact on the exact location
of the severe weather threat on Tuesday. However, regardless of Day
4 convective evolution, there will likely be a region with a more
focused severe weather threat on Day 5/Wednesday where moderate to
strong instability exists ahead of strengthening mid-level flow and
a mid-level trough which will move across the southern Plains. 15% probabilities have been added for Day 5 from North Texas to the
ArkLaTex where this location of greatest severe weather threat
appears most likely at this time.

..Bentley.. 04/26/2025

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ACUS48 KWNS 270723
SWOD48
SPC AC 270721

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 AM CDT Sun Apr 27 2025

Valid 301200Z - 051200Z

...DISCUSSION...
...Day 4/Wednesday - North Central to Northeast Texas...
A mid-level trough will eject across the southern Plains on Day
4/Wednesday. Forecast guidance still shows some timing difference
which affect the location of the surface low and thus the region of
the greatest severe weather threat. However, at this time, the area
along and south of the Red River to east-central Texas remains the
most likely location to receive some severe weather regardless of
the exact solution.

Moderate instability and an uncapped environment will support storm
development during the day on Wednesday. At this time, it appears
widespread convection amid a very moist profile could result in HP
storms in close proximity with eventual growth into a MCS. Forecast
soundings show favorable low-level shear which would support some
tornado threat. However, the aforementioned storm mode concerns
could limit this threat despite the favorable wind profile.

...Day 5/Thursday - Mid Mississippi Valley...
As a mid-level trough advances from the southern Plains to the Great
Lakes on Thursday, a surface low will also develop and continue
northeast. The strength and location of this surface low are
uncertain at this time due to differing evolution of the mid-level
pattern. Warm-sector destabilization also remains highly variable.
If a solution such as the GFS solution verifies, then a greater
severe weather threat will likely exist across parts of Tennessee
and northern AL/MS into parts of the Ohio Valley. However, if the
ECMWF instability verifies, the likelihood of widespread severe
weather goes down significantly. No probabilities have been added
for Day 5 yet, but if details become more clear and favorable,
probabilities may eventually be needed.

..Bentley.. 04/27/2025

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ACUS48 KWNS 280837
SWOD48
SPC AC 280835

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0335 AM CDT Mon Apr 28 2025

Valid 011200Z - 061200Z

...DISCUSSION...
The extended period will begin with broad troughing across the
eastern US and a surface low tracking northeastward across the Great
Lakes. A cold front will stretch from the northeastern US southward
into the southern Plains, shifting eastward on D5/Friday across the
Ohio Valley into the southeastern US. Beyond D5/Friday, heights will
begin to rise across the Plains as an upper level high strengthens,
which will limit the severe threat through the end of the extended.

...D5/Friday - Tennessee and Ohio Valley...
On D5/Friday, thunderstorm development is expected along the cold
front across portions of the Ohio Valley into the southern
Mississippi Valley. Model solutions differ on how much instability
will be available across Tennessee into the Ohio Valley, where the
strongest flow aloft will reside. There appears to be little overlap
between the better flow aloft and any meaningful instability, which
keeps probabilities too low to include areas in the extended.
However, some instances of wind and hail from stronger storms will
be possible across portions of Tennessee into Ohio.

...D6/Saturday - Southwest Texas...
Thunderstorm development is possible along the dryline in
southwestern Texas on D6/Saturday. During this period, heights aloft
will be rising, which will likely work to limit overall coverage of thunderstorm activity. Nonetheless, a few isolated supercells may
develop with potential for large hail and severe wind. Overall,
limited coverage does not warrant inclusion of probabilities.

..Thornton/Bentley.. 04/28/2025

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ACUS48 KWNS 280858
SWOD48
SPC AC 280857

Day 4-8 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0357 AM CDT Mon Apr 28 2025

Valid 011200Z - 061200Z

CORRECTED FOR INCORRECT DAY REFERENCE

...DISCUSSION...
The extended period will begin with broad troughing across the
eastern US and a surface low tracking northeastward across the Great
Lakes. A cold front will stretch from the northeastern US southward
into the southern Plains, shifting eastward on D4/Thursday across
the Ohio Valley into the southeastern US. Beyond D4/Thursday,
heights will begin to rise across the Plains as an upper level high strengthens, which will limit the severe threat through the end of
the extended.

...D4/Thursday - Tennessee and Ohio Valley...
On D4/Thursday, thunderstorm development is expected along the cold
front across portions of the Ohio Valley into the southern
Mississippi Valley. Model solutions differ on how much instability
will be available across Tennessee into the Ohio Valley, where the
strongest flow aloft will reside. There appears to be little overlap
between the better flow aloft and any meaningful instability, which
keeps probabilities too low to include areas in the extended.
However, some instances of wind and hail from stronger storms will
be possible across portions of Tennessee into Ohio.

...D5/Friday - Southwest Texas...
Thunderstorm development is possible along the dryline in
southwestern Texas on D5/Friday. During this period, heights aloft
will be rising, which will likely work to limit overall coverage of thunderstorm activity. Nonetheless, a few isolated supercells may
develop with potential for large hail and severe wind. Overall,
limited coverage does not warrant inclusion of probabilities.

..Thornton/Bentley.. 04/28/2025

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ACUS48 KWNS 290856
SWOD48
SPC AC 290854

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0354 AM CDT Tue Apr 29 2025

Valid 021200Z - 071200Z

...DISCUSSION...
The severe potential remains limited through the day 4-8 period. On
D4/Friday, an upper level trough will be located across the eastern
US with strengthening upper level ridging across the western US into
the Rockies. Along the dryline in far western Texas, a few
thunderstorms capable of large hail will be possible. This threat
may be limited in duration and coverage by the southward moving cold
front expected to extend from the southern Plains into the
northeastern US. As this front shifts southward and a surface high
builds in across the central US D5/Saturday into D6/Sunday, moisture
will be scoured out of much of the CONUS limiting the severe threat.


As the surface high shifts eastward across the Midwest, slow
moisture return will begin across the southern Plains late D6/Sunday
into D7/Monday. During this period, the next upper-level wave will
be deepening across the western US. As this system evolves, severe
potential may return late in the period across portions of the
southern and central Plains.

..Thornton/Bentley.. 04/29/2025

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ACUS48 KWNS 300805
SWOD48
SPC AC 300803

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0303 AM CDT Wed Apr 30 2025

Valid 031200Z - 081200Z

...DISCUSSION...
A cold front will shift southward across the southern US at the
start of the extended period, scouring out much of the moisture
across the CONUS. An upper level ridge is expected to strengthen
across the central US while weak troughing continues in the
northeast. This pattern will limit severe potential across the CONUS
through the weekend.

As a surface high across the Plains strengthens and shifts eastward
into the Midwest, return flow from the Gulf will bring moisture back
in across the central and southern Plains starting D6/Monday. A
trough will strengthen across the western US D5/Sunday before
ejecting into the Plains sometime D7/Tuesday into D8/Wednesday. This
would likely bring a return to chances for severe storms across some
portion of the southern and central Plains. There is uncertainty in
how far northward moisture return will reach and where exactly
surface features will be during this time period. This precludes the
need to include areas at this time.

..Thornton/Bentley.. 04/30/2025

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ACUS48 KWNS 010856
SWOD48
SPC AC 010855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CDT Thu May 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
High pressure will dominate much of the eastern CONUS at the start
of the extended period. This will shift most moisture into the
Atlantic/Gulf of America. The only exception will be across Texas
where east-southeasterly flow will advect richer low-level moisture
into the southern High Plains. This will be the focus for any
potential severe storms on Day 4/Sun and Day 5/Mon. However,
specific during this period, and particularly beyond, are quite
nebulous. The ECMWF cuts off an upper low across the Ohio Valley
vicinity on Saturday Night while the GFS waits to cut off the
upper-low across the Southeast US on Monday/Tuesday.

Farther west there is more consistency in the upper pattern with a
cutoff low in the Southwest vicinity. Enhanced southwesterly flow
could result in several days of severe weather in the southern
Plains. However, moisture remains uncertain due to aforementioned timing/location differences for the mid-level trough in the East.
The GFS solution results in a more progressive cold front which
clears out most of the greater moisture from the Gulf. However, the
ECMWF stalls the front across the central Gulf which leaves a
reservoir of rich theta-e which can be advected across Texas and
vicinity during the early-mid part of next week. Therefore,
predictability remains too low for probabilities at this time, but
once the upper-level pattern becomes more clear, probabilities may
be necessary.

..Bentley.. 05/01/2025

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