004
ACUS48 KWNS 210852
SWOD48
SPC AC 210850
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0350 AM CDT WED MAY 21 2025
VALID 241200Z - 291200Z
..DISCUSSION
SEVERE WEATHER IS POSSIBLE ACROSS PORTIONS OF THE CENTRAL PLAINS ON
SATURDAY AND SUNDAY AS A MID-LEVEL TROUGH EMERGES FROM THE ROCKIES
INTO THE PLAINS. UPPER 60S TO LOW 70S DEWPOINTS WILL RESULT IN
STRONG TO VERY STRONG INSTABILITY SOUTH OF A FRONTAL ZONE. THIS
FRONT WILL INITIALLY BE STATIONARY ACROSS KANSAS ON SATURDAY BEFORE
STARTING TO ADVANCE SOUTH SATURDAY NIGHT AND SUNDAY. GIVEN THE
INSTABILITY AHEAD OF THIS FRONT, WIDESPREAD STORM DEVELOPMENT IS
LIKELY. HOWEVER, THE SEVERITY OF THIS CONVECTION REMAINS
QUESTIONABLE. THE OPERATIONAL GFS IS THE MOST AGGRESSIVE WITH SEVERE
WEATHER POTENTIAL AS IT MAINTAINS TROUGHING INTO THE PLAINS WITH
SOUTHWESTERLY FLOW AROUND 40 KNOTS FORECAST ACROSS THE FRONTAL ZONE
WHICH SHOULD PROVIDE AMPLE SHEAR FOR SEVERE STORMS GIVEN THE LIKELY
INSTABILITY THAT WILL BE IN PLACE. HOWEVER, THIS APPEARS TO BE AN
OUTLIER WITH WEAKER, MORE ZONAL FLOW PREFERRED BY THE ECMWF AND THE
ECS AND GEFS. DUE TO THIS UNCERTAINTY REGARDING THE MID-LEVEL
TROUGHING AND SHEAR ACROSS THE WARM SECTOR, SEVERE WEATHER
PROBABILITIES ARE NOT WARRANTED AT THIS TIME.
HIGH PRESSURE WILL BUILD INTO MUCH OF THE EASTERN CONUS ON DAY
6/MONDAY AND PERSIST FOR MUCH OF THE WEEK. THIS WILL SHUNT A FRONTAL
ZONE AND THE BETTER MOISTURE CLOSER TO THE GULF COAST, REMOVED FROM
THE STRONGER MID-LEVEL WESTERLIES. THEREFORE, THUNDERSTORMS WILL BE
LIKELY ALONG THIS FRONTAL ZONE THROUGH THE WEEK, BUT ORGANIZED
SEVERE STORMS ARE NOT EXPECTED TO BE THAT WIDESPREAD.
..BENTLEY.. 05/21/2025
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