(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 270721
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
CLICK TO GET WUUS48 PTSD48 PRODUCT