(All days are valid from 12 UTC - 12 UTC the following day)
Note: A severe weather area depicted in the Day 4-8 period indicates 15%, 30% or higher probability for severe thunderstorms within 25 miles of any point.
PREDICTABILITY TOO LOW is used to indicate severe storms may be possible based on some model scenarios. However, the location or occurrence of severe storms are in doubt due to: 1) large differences in the deterministic model solutions, 2) large spread in the ensemble guidance, and/or 3) minimal run-to-run continuity.
POTENTIAL TOO LOW means the threat for a regional area of organized severe storms appears unlikely (i.e., less than 15%) for the forecast day.
Forecast Discussion
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 020900
SPC AC 020900
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Wed Apr 02 2025
Valid 051200Z - 101200Z
...DISCUSSION...
The mid-level flow pattern will undergo significant amplification
over the next several days as a large western US trough begins to
move eastward. Very rich moisture will support widespread
thunderstorm potential across parts of the Southeast and eastern US
through the weekend.
...D4/Saturday Mid South...
The upper low over northern Mexico will continue to amplify as it
begins ejecting eastward across the lower and mid MS Valley. A
strong 100+ kt jet will move east of the trough and overspread a
relatively broad warm sector across the Sabine and MS Valleys into
parts of TN/KY. Unseasonably rich moisture from several days of
southerly flow will be in place ahead of a surface low and cold
front. One or more rounds of severe storms, including supercells,
appears likely from eastern TX into AR, LA, and MS through the day.
All hazards will be possible. Storms should eventually grow upscale
into a line or cluster and spread eastward overnight into parts of
AL, FL, and GA.
The northern bound of the risk area across the TN Valley and into
the OH valley appears somewhat conditional. Multiple preceding days
of storms may limit the northern extent of the deeper moisture and
buoyancy. However, some severe risk likely exists given the
intensity of the low-level jet and abundance of moisture.
...Day 5...
The severe threat is likely to carry over from Day 4 in the form of
a squall line, as the upper wave gradually devolves into a broader
positive-tilt trough. Strong mid-level flow and ascent will persist
over a broadening warm sector across the Southeast. While lapse
rates appear weak from several days of convection, some severe risk
is possible. The intensity of the severe risk will be heavily
dependent on the convective evolution from the prior day 4 which is
very unclear at the moment. Will add a 15% area across parts of AL,
FL, GA and SC where the best overlap of mid-level flow and robust
moisture are expected to support potential for damaging gusts.
A severe risk may also develop across parts of the Carolinas and mid
Atlantic Day5/Sunday. As the upper wave lifts to the north, ascent
will overspread returning surface moisture as far north as southern
PA. It is unclear how much buoyancy will be present with the
potential for widespread clouds. However, strong flow fields will be
available to any convection that can develop.
...D6+...
Offshore flow and high pressure will begin to dominate the extended
period as mid-level ridging intensifies over the center of the
country. Much cooler and stable conditions behind the advancing cold
front appear likely to temporarily end broader potential for severe
storms through early next week.
..Lyons.. 04/02/2025
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