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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ACUS48 KWNS 020845
SWOD48
SPC AC 020844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Fri May 02 2025

Valid 051200Z - 101200Z

...DISCUSSION...
...Day 4/Monday - Southern High Plains...
Lee cyclogenesis will strengthen on Monday in the southern High
Plains as a mid-level trough advects eastward. As this occurs, rich
low-level moisture will advect into West Texas which will result in
strong instability as temperatures continue to cool aloft. Expect
scattered thunderstorm development along the dryline during the afternoon/evening. However, more widespread storm development is
likely after 00Z as the low-level jet strengthens across West Texas.
Initial supercells will have a threat for all severe weather hazards
before eventual upscale growth into a MCS likely results in a
greater severe wind threat.

...Day 5/Tuesday - Central/East Texas into Louisiana...
Day 4 thunderstorms will likely be ongoing at the beginning of the
period along a frontal zone across central/East Texas and persist
eastward through the day. Destabilization remains questionable as
strong high pressure and the low-latitude nature of the mid-level
trough may limit northward movement of the warm front. The potential
for this front to be stationary, in addition to widespread
convection/cloud cover concerns along the front, preclude severe
weather probabilities at this time. However, there will likely be a
corridor along the frontal zone with some greater severe weather
threat which may become more clear as the event draws closer.

Additional severe storms will be possible Day 6 and 7 along the
frontal zone/composite outflow in Texas, but the location of this
feature and degree of destabilization along it will be highly
dependent on prior days convective activity. For these reasons, no probabilities have been added at this time.

..Bentley.. 05/02/2025

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ACUS48 KWNS 030858
SWOD48
SPC AC 030856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Sat May 03 2025

Valid 061200Z - 111200Z

...DISCUSSION...
...D4/Tuesday...
The upper low in the Four Corners region will make more progress
eastward on Tuesday. It will be weakening with time, however. The
surface pattern in turn will be somewhat disorganized. At least some southeasterly winds at the surface will continue to advect richer
moisture into Central and East Texas. A warm front will be
positioned from the central Gulf coast northwestward to near the Red
River. A composite front/dryline is also expected in Central Texas.
The ECMWF is the most aggressive with early period precipitation and
has the farthest south cluster/MCS comparatively as well. Given the
forcing from an ejecting shortwave trough and stronger 850 mb flow
into the warm front, this solution appears to be more plausible at
this point. This would lead to considerable uncertainty as to the
degree of destabilization in parts of Central Texas into the Sabine
Valley. That said, wind fields will be supportive of severe storms.
Should more limited precipitation occur, severe storms could be more
focused along the warm front and dryline. Confidence in placement of
key features remains too low for highlights at this time.

...D5/Wednesday...
The upper-level low will become an open wave by Wednesday.
Significant loss of amplitude is also expected by this time. A belt
of stronger mid-level winds will remain over coastal Texas into the
central and parts of the eastern Gulf coast. With this upper-level
and surface pattern, it is not clear how far inland greater buoyancy
will reach. This uncertainty coupled with storm development not
being favorably timed diurnally reduces confidence in highlighting
any corridors of greater severe potential.

...D6/Thursday into the Weekend...
The elongated upper trough is forecast to become another weak cutoff
low in the lower Mississippi Valley. In the West, an upper-level
ridge will build and move over the Plains by the weekend. This
pattern does not suggest a significant risk of organized severe
storms, though mesoscale/conditional areas may eventually become
evident.

..Wendt.. 05/03/2025

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ACUS48 KWNS 040842
SWOD48
SPC AC 040841

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0341 AM CDT Sun May 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
The upper-level low in the Southwest will begin to weaken on
Wednesday. Thereafter, it will make slow eastward progress before
becoming a weak cutoff low over the lower Mississippi Valley by the
weekend. This upper-level pattern will help push a surface boundary
along and offshore of the Gulf Coast. As the weekend progresses,
this boundary will move further offshore along with the weak upper
low. In the West and Plains, upper-level ridging will become
prominent and remain in place into the following week.

Some moderate mid-level winds will likely remain along the Gulf
Coast at least until this coming weekend. With some lingering
moisture in the coastal regions, its possible that areas of
localized severe risk will develop. However, the overall pattern
will not be favorable for any areas of organized/predictable severe
risk.

..Wendt.. 05/04/2025

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ACUS48 KWNS 050831
SWOD48
SPC AC 050830

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CDT Mon May 05 2025

Valid 081200Z - 131200Z

...DISCUSSION...
From Thursday into the weekend, the upper-level pattern will be
characterized by an elongated trough in the East and a building
ridge in the West. With this weakly blocking pattern, slow
progression of these features can be expected. With the trough in
the East, moisture will be present south of a surface boundary
across parts of the Southeast and eventually into the Florida
Peninsula. Though organized severe potential appears low with this
activity, enough remnant mid-level flow could promote localized
strong storms. By next week, models currently suggest some troughing
is possible in the West. With preceding days of offshore winds
across the western Gulf, moisture quality ahead of any potential
trough is likely to be low.

..Wendt.. 05/05/2025

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ACUS48 KWNS 060856
SWOD48
SPC AC 060855

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0355 AM CDT Tue May 06 2025

Valid 091200Z - 141200Z

...DISCUSSION...
Late this week, an elongated upper trough from the Southeast into
the Northeast will evolve into a cutoff low centered roughly on the
Gulf Coast with stronger cyclonic flow remaining in the Northeast.
An upper-level ridge will continue to build in the West and Plains
and shift eastward into early next week. With the weak upper low
near the Gulf, this will spur repeated days of convection across
part of the Southeast and Florida. It is possible low-end severe
potential will exist with some of this activity until low/mid-level
lapse rates become poor. However, substantive severe threats are not
expected.

With the ridge building over the cutoff low, it will be slow to move
eastward. Model guidance suggests that this feature will reach the
East Coast around the middle of next week. At the same time, a
strong upper trough is expected to move into the West. Moisture
return into the Plains will begin as the trough moves eastward. That
said, at least a few days worth of offshore flow in the western Gulf
will likely limit the initial quality of that moisture return. The
potential for severe weather with the incoming western trough
remains uncertain at this point in time.

..Wendt.. 05/06/2025

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ACUS48 KWNS 070814
SWOD48
SPC AC 070813

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0313 AM CDT Wed May 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
From this weekend through early next week, an upper-level low will
be situated in the lower Mississippi Valley into the northern Gulf.
This feature will drive repeated days of convection within parts of
the Southeast into the Florida Peninsula. Lower-end severe potential
may occur with this activity, but how organized/intense it will be
is not certain. The upper-level low will become more progressive and
lift northeastward by the middle of next week. Shortwave ridging
aloft will move through the Plains into the Southeast in advance of
a western trough. With the presence of the upper low over the Gulf
Coast region, there will be offshore flow in the western Gulf for a
few days before moisture returns northward again in response to the
mid-week trough.

The largest uncertainty with this system will be the moisture
quality. Secondly, models currently project the strongest forcing to
be within the central/northern Plains, farther away from the
moisture plume moving north. At least as currently forecast, strong southwesterly/westerly winds aloft should overspread the
southern/central Plains by late next week. This particular trend in
guidance is recent and confidence is accordingly low, but model
trends will continue to be monitored in the coming days.

..Wendt.. 05/07/2025

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ACUS48 KWNS 080858
SWOD48
SPC AC 080856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Thu May 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
...Southeast into Mid-Atlantic...
By early next week, the cutoff upper low is forecast to become more
progressive and move northeastward. As this occurs, convection will
begin to overspread more of the Southeast into southern portions of
Florida and eventually the Mid-Atlantic. At this time, the potential
for several days of precipitation/cloud cover to impact surface
heating does not suggest a substantive severe threat will exist.
Furthermore, mid-level flow will weaken with time as the low lifts
northeast. Moderate mid-level winds will remain over Florida until
midweek. While Central/South Florida could see relatively higher
severe potential on Tuesday into Wednesday, models still show
limited destabilization on account of the uncertain surface heating
described earlier.

...Northern Rockies/Plains...
Strong upper-level winds will overspread the northern Rockies on
Sunday. Mid-level ascent should be sufficient for potentially
scattered storm development. Moisture still appears it may be
limited, but some threat for severe wind gusts may accompany storms
on Sunday in parts of southwest into central Montana. Uncertainty in
storm intensity precludes highlights, however. As the trough
continues to shift eastward, moisture return may be sufficient
enough to support some potential for severe storms mid to late next
week in parts of the Dakotas into Iowa/Minnesota. Aside from
questions about low-level moisture, timing and structure of the
trough varies in guidance and makes the coverage/intensity of storms
too uncertain for highlights.

...Central/southern Plains...
Model guidance continues to show the potential for a trough to
impact these regions by mid/late next week. Timing and position of
the stronger winds/greatest forcing continues to shift spatially,
however. Given that both the GEFS/EPS ensembles show a trough in the
mean next week does give some confidence in the general pattern.
Available ML guidance has also picked up on the pattern shift and
started to show an increased signal for severe potential. However,
significant uncertainties remain. With the cutoff nature of the
upper low in the lower Mississippi Valley, it is a feature that is
not predictable in terms of how fast it will depart. If guidance is
correct, it will move out right as the trough nears the Plains. This
leaves little time for a deep moist layer to develop and move
northward after a few days of offshore winds in the western Gulf.
Low-level moisture forecasts ahead of the trough do show mid/upper
60s F dewpoints. That said, the moisture profile in the vertical is
quite poor. It is not until next weekend that a signal for deeper
moisture is evident in model guidance. Lastly, shortwave ridging
will be in place ahead of the trough. Temperatures aloft do not
appear likely to appreciably cool given the current forecast
evolution of the trough and capping will be a concern. Trends in
guidance will continue to be monitored.

..Wendt.. 05/08/2025

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ACUS48 KWNS 090901
SWOD48
SPC AC 090859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Fri May 09 2025

Valid 121200Z - 171200Z

...DISCUSSION...
Based on the latest medium-range guidance, it appears that
large-scale mid/upper troughing will continue digging inland of the
Pacific coast, before gradually turning eastward toward the Rockies
during the early portion of next week. While this probably will be
accompanied by the development of modestly deep surface troughing
across the Great Plains, appreciable low-level moisture return, in
the wake of a mid-level low/trough slowly accelerating northeast of
the lower Mississippi Valley, through parts of the Mid South and
Ohio Valley, remains uncertain.

Even into mid-week, when it appears that the troughing may begin to
emerge from the Intermountain West/Rockies, while the downstream
troughing only slowly progresses across the Mid Atlantic, moisture
return (and destabilization) to the vicinity of the stronger forcing
for ascent may remain a potential limiting factor to severe
thunderstorm development.

Toward next Thursday/Friday, there does appear consensus that
stronger destabilization may begin to become better coupled with
large-scale forcing for ascent across the upper Mississippi
Valley/Midwest into Ohio Valley, as the mid-level troughing
progresses northeastward and eastward, around the periphery of
mid/upper ridging building north-northeast of the lower Mississippi
Valley. This appears to include at least a conditional risk for
organized severe convection, including a few supercells. Although
lingering uncertainties preclude introducing 15 percent or greater
severe probabilities at this time, this may change in later outlooks
for this period.

..Kerr.. 05/09/2025

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ACUS48 KWNS 100902
SWOD48
SPC AC 100900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Sat May 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Medium-range guidance indicates that a generally amplified, split
mid/upper flow will persist across the mid-latitude Pacific through
North America next week. It appears that this will include at least
a couple of significant troughs digging inland of the U.S. Pacific
Coast. The first may already be in the process of developing
eastward across the Intermountain West early in this period
(Tuesday), before progressing across the Rockies, Great Plains and
Mississippi Valley during the middle through latter portion of next
week. This may be followed by another significant trough digging
inland of the Pacific coast by early next weekend.

The lead trough will be relatively close on the heels of the
remnants of an initially broad quasi-stationary/cut-off low, which
may only slowly progress east of the Mississippi Valley through
Atlantic Seaboard during the early to middle portion of next week.
Low-level moisture return, in the wake of this perturbation and
ahead of the mid-level trough emerging from the West, may continue
to be impacted across at least parts of the Great Plains into mid
week. Thereafter, there appears a general consensus that there will
be a better coupling of large-scale forcing for ascent, aided by
surface cyclogenesis, with a notable increase in low-level moisture
and destabilization across the lower Missouri Valley into the Upper
Midwest and lower Ohio Valley by late next Thursday into Thursday
night. In the presence of strong shear, it appears that this
environment could become supportive of supercells and/or one or two
organizing severe storm clusters.

Machine learning output and other guidance suggests that potential
for strong to severe thunderstorms could persist and potentially
become more widespread across the Ohio Valley into Mid Atlantic, and
southern Great Plains, next Friday and Saturday. However,
uncertainties remain too large at this time to introduce greater
than 15 percent severe probabilities.

..Kerr.. 05/10/2025

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ACUS48 KWNS 110902
SWOD48
SPC AC 110900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Sun May 11 2025

Valid 141200Z - 191200Z

...DISCUSSION...
Latest medium-range output remains generally similar to prior runs
concerning the pattern evolution Wednesday into Thursday. A
significant short wave trough emerging from the Intermountain West
is forecast to support modest cyclogenesis across the central and
northern Great Plains through the mid/upper Mississippi Valley
vicinity. It appears that this probably will be accompanied by
increasing potential for strong to severe thunderstorm development,
with severe probabilities maximizing across parts of the Midwest
late Thursday into Thursday night, as the stronger large-scale
forcing for ascent becomes better coupled with substantive
boundary-layer moistening and destabilization. Aided by steep lower/mid-tropospheric lapse rates associated with elevated
mixed-layer air, and moderate to strong low-level and deep-layer
shear, it appears that the environment will become conducive to the
evolution of an upscale growing and organizing convective system.
But initial convection may include supercells posing a risk for
large hail and a couple of tornadoes, before damaging wind gusts
become the predominate severe hazard.

Based on the subsequent pattern evolution, it appears that this
convection could persist into, or re-intensify, Friday across parts
of the mid/upper Ohio Valley, with additional upscale growing
convection evolving along a stalling trailing cold front near the
southern edge of the stronger westerlies. Into next weekend,
renewed cyclogenesis appears possible along the trailing flank of
the front across the south central Great Plains, where additional
strong to severe thunderstorm development may focus along a
developing warm front, and a developing dryline southward through
the plains, as the warm sector destabilizes with increasing Gulf
moisture return.

However, by late Thursday into Friday, and beyond, these
developments remain much more unclear, as spread among and within
the various medium-range models begins to increase. Substantive
differences begin to develop concerning the progressiveness of the
lead trough, and a trailing short wave trough emerging from the
mid-latitude Pacific. The uncertain impacts of potentially multiple
evolving large convective clusters on succeeding days adds to low predictability.

..Kerr.. 05/11/2025

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ACUS48 KWNS 120901
SWOD48
SPC AC 120859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon May 12 2025

Valid 151200Z - 201200Z

...DISCUSSION...
An active period of severe weather is anticipated through early next
week based on recent trends in long-range guidance. A transition to
a progressive upper-level regime is expected over the next seven
days as a series of upper waves traverse the CONUS with favorable
wavelengths for air mass/moisture recovery into central portions of
the CONUS. Although both the GFS and ECMWF (and their respective
ensemble families) show similar synoptic evolutions through the
extended period, predictability in any severe threat currently
appears greatest on D4/Thursday and D5/Friday.

...D4/Thursday...
The upper-level trough currently over the Pacific Northwest is
forecast to eject into the upper MS River Valley through the day
Thursday with an attendant surface low deepening across the upper MS
Valley. A Pacific front is forecast to push east into an expanding
warm sector that should span from the MS River into the upper Great
Lakes and OH River Valley. Strong mid-level flow orthogonal to the
front should generally promote discrete/semi-discrete convection by
late afternoon on the eastern fringe of a stout EML. The consistent
signal for QPF within the warm sector coincident with 50-60 knot
mid-level flow and the intensifying nature of the synoptic low
suggests that a widespread severe weather event is possible and may
expand further east than depicted in previous forecasts. Despite
these trends, regional discrepancies among guidance limit confidence
in where the more robust severe corridors will become established.
Notable factors limiting confidence are the potential for strong
capping across much of the OH Valley and a faster progression of the
surface low/front in recent GFS/GEFS solutions (which typically
exhibit a fast bias at this range).

...D5/Friday...
The Pacific front/outflow associated with D4/Thursday's convection
is expected to stall across the lower OH Valley/mid-MS Valley before
gradually returning north as an effective warm front on Friday.
Ensemble guidance shows a reasonably strong signal for dewpoints in
the mid/upper 60s (potentially into the low 70s) along and south of
this boundary by peak heating. A mid-level impulse propagating over
the region should maintain elongated hodographs and provide
sufficient lift for thunderstorm development along the boundary.
This synoptic regime suggests that one or more organized
clusters/linear segments may propagate along the boundary and into
parts of the mid-MS Valley, lower OH Valley, and potentially into
the TN Valley. Given the thermodynamic and kinematic environment
forecast by ensemble guidance, such a cluster/line will likely pose
a severe threat. A 15% risk area has been introduced where the QPF
signal associated with this regime has been most consistent over
recent model runs, but further forecast refinements are expected.

..Moore.. 05/12/2025

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ACUS48 KWNS 130859
SWOD48
SPC AC 130858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Tue May 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
An active period of severe weather is anticipated through early next
week as a pair of upper-level troughs traverse the U.S. and will be
favorably timed to allow moisture recovery into central/southern
portions of the CONUS. The upper trough currently over the Pacific
Northwest is forecast to migrate into the Great Lakes region by this
weekend. In the wake of this feature, a second long-wave trough will
begin to deepen across the West before migrating into the Plains by
early/mid next week with attendant chances for strong/severe
thunderstorms.

...D4/Friday...
A stalled boundary will likely be draped from the Ozarks into the OH
Valley at the beginning of the forecast period. A weak,
low-amplitude mid-level perturbation emanating out of the central
Plains will promote secondary surface low development across the
southern Plains that will maintain southerly low-level flow. As
such, some northward migration of the boundary as an effective warm
front appears probable. Thunderstorm development along the boundary
is anticipated by late afternoon, and 40-50 knot mid-level flow
oriented along the frontal zone should promote initially
discrete/semi-discrete cells with the potential for upscale growth
into one or more organized clusters. Some disagreement in exactly
where the corridor of highest severe threat will become established
persists and is associated with the coverage and intensity of
ongoing convection Friday morning. Recent GFS/GEFS runs hint that
more isolated convection early Friday will allow for more aggressive
northward advancement of the front, while ECMWF solutions hint at
slower northward progression of the boundary. The 15% risk area has
been expanded to best encompass the overlap between these two
dichotomous solutions.

...D6/Sunday to D8/Tuesday...
A deepening upper level trough over the western states will promote
several days of lee troughing/cyclogenesis across the southern to
central High Plains beginning this weekend. This will allow for more
seasonal moisture return into the Plains with most ensemble members
showing dewpoints climbing into the low to mid 60s by D6/Sunday
afternoon across TX, OK, and southern KS. Deterministic solutions
continue to vary regarding the exact timing and evolution of the
upper-level wave (and any embedded impulses), but the general
consensus is that severe thunderstorms will be possible as
upper-level disturbances overspread the Plains and promote eastward
mixing of the dryline into an increasingly buoyant warm sector.
Confidence on any particular day remains too limited for risk
probabilities, but the overall synoptic regime and convective QPF
signals in ensemble guidance suggest that the potential for multiple
rounds of severe thunderstorms is increasing for the
southern/central Plains beginning D6/Sunday through D8/Tuesday.

..Moore.. 05/13/2025

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ACUS48 KWNS 140855
SWOD48
SPC AC 140853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Wed May 14 2025

Valid 171200Z - 221200Z

...DISCUSSION...
An active period of severe weather remains likely through the
weekend and into early next week for portions of the central CONUS.
A weakening upper trough is forecast to migrate across the Northeast
late this weekend as a second upper wave begins to amplify over the
western states. This upper regime will favor surface pressure falls
across the High Plains that will promote south/southeasterly return
flow into the southern/central Plains through early next week.
Severe thunderstorm chances will increase as preceding upper
disturbances and the primary upper wave eject into the Plains over
the warm sector. While severe weather chances are anticipated most
days through the extended period, confidence in more focused, synoptically-driven corridors is currently greatest on D5/Sunday and
D6/Monday across the southern Plains.

...D5/Sunday to D6/Monday...
Increasing southwesterly flow aloft over the southern/central
Rockies will promote lee cyclogenesis across the central High Plains
beginning D4/Saturday through D7/Monday. This will foster moisture
return into northern TX, OK, and southern KS as a warm front lifts
north. Long-range ensemble guidance suggests dewpoints ranging from
the mid 60s to low 70s are likely by Sunday afternoon across the
southern High Plains to the east of a sharpening dryline. Recent
GFS/GEFS solutions have come into better alignment with ECMWF/EPS
runs that depict a leading impulse within the subtropical jet
overspreading the southern High Plains late Sunday afternoon.
Enhanced westerly low- to mid-level flow coupled with ascent
associated with the upper feature should promote eastward mixing of
the dryline with attendant chances for thunderstorm development
within a buoyant and strongly sheared environment.

The ejection of the primary trough axis on D6/Monday should result
in more widespread 50+ knot mid-level flow overspreading much of
OK/KS. The eastward migration of the surface low and trailing
dryline through the day should provide adequate forcing for ascent
for thunderstorm development within a buoyant and strongly sheared
environment, which should promote an organized, and potentially more widespread, severe threat.

More specific mesoscale details for both days remain unclear at this
range, but the general alignment of global deterministic/ensemble
guidance regarding the overall synoptic regime and convective
environment, combined with a consistent QPF signal on both days,
suggests predictability is high enough to introduce risk
probabilities.

...D4/Saturday...
A residual cold front associated with a weakening surface low over
the northern CONUS is expected to be draped from the southern
Appalachians southwestward into the mid-MS Valley/Ozark Plateau
region. Sufficient buoyancy and strong zonal flow aloft will likely
support organized convection along the frontal zone. While some
severe threat is anticipated, mid-level ridging and lingering
convection at the start of the day limit confidence/predictability
in where the better mesoscale corridors for severe convection will
become established.

...D7/Tuesday...
Some severe threat is expected to persist into Tuesday as a surface
low and attendant trough/dryline migrate east towards the Midwest.
Ensemble guidance hints at strong/severe thunderstorm potential
across parts of AR, MO, and the lower OH Valley, but spread among
deterministic solutions and the potential for lingering convection
from D6/Monday limits confidence at this range.

..Moore.. 05/14/2025

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