ACUS02 KWNS 210602

SWODY2

SPC AC 210601



Day 2 Convective Outlook  

NWS Storm Prediction Center Norman OK

0101 AM CDT Sat Mar 21 2026



Valid 221200Z - 231200Z



...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF

THE OHIO VALLEY...



...SUMMARY...

Severe thunderstorms with large hail and severe wind gusts are

expected on Sunday afternoon and evening across parts of the Ohio

Valley.



...Ohio Valley/Mid Mississippi Valley...

At mid-levels on Sunday, an amplifying trough will move quickly

east-southeastward across the north-central U.S, as an associated

jet streak translates eastward into the southern Great Lakes. At the

surface, a cold front will advance southward into the Ohio Valley.

South of the front, moderate instability will develop across a moist

airmass by early afternoon, with surface dewpoints in the lower to

mid 60s F. Warming surface temperatures and increasing low-level

convergence will result in convective initiation along parts of the

front during the mid to late afternoon. Storm coverage is forecast

to gradually increase as several clusters or line segments with a

severe threat move southeastward across the Ohio Valley during the

late afternoon and early evening.



During the afternoon from Cincinnati to Pittsburgh, forecast

soundings gradually increase MLCAPE in the 1500 to 2000 J/kg range.

Forecasts just ahead of the front suggest that winds will be veered

to the southwest near the surface, but that strong speed shear will

exist in the lower to mid-levels. 0-6 km shear is forecast to range

from 40 to 50 knots, which should be favorable for severe

thunderstorm development. 700-500 mb lapse rates in the 7.0 to 7.5

C/km range should support supercells with large hail. The supercell

threat is expected to be greatest early in the event, when cells are

more likely to be discrete. A threat for severe wind gusts is also

expected. The wind-damage threat should be concentrated along short

line segments that form in the late afternoon and early evening. A

marginal tornado threat will also be possible.



Further west-southwest into the lower Ohio Valley and mid

Mississippi Valley, the models are forecasting a stout capping

inversion to the south of the front over much of the warm sector.

Near the front in the early evening, the cap is forecast to weaken.

This combined with increasing low-level convergence near the front

should be enough for isolated convective initiation. A marginal

threat for hail and severe wind gusts would be possible with the

stronger cells that can initiate and persist.



..Broyles.. 03/21/2026



$$