965
ACUS01 KWNS 231251
SWODY1
SPC AC 231250
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0750 AM CDT THU APR 23 2026
VALID 231300Z - 241200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS
AFTERNOON/EVENING FOR EASTERN KANSAS INTO EXTREME NORTHERN
OKLAHOMA...
..SUMMARY
SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND
EVENING FROM THE SOUTHERN AND CENTRAL PLAINS INTO THE LOWER TO MID
MISSOURI VALLEY, AND UPPER MISSISSIPPI VALLEY. TORNADOES, LARGE HAIL
AND SEVERE WIND GUSTS WILL BE POSSIBLE.
..MN/IA TO KS/NORTHERN OK THIS AFTERNOON INTO TONIGHT
THE INTERACTION OF A SOUTHEASTWARD MOVING MIDLEVEL TROUGH OVER
SOUTHERN BC/AB AND A NORTHEASTWARD MOVING TROUGH OVER THE WESTERN
DAKOTAS WILL LEAD TO THE FORMATION OF A DEEP CLOSED LOW OVER
SOUTHERN SK. AN ASSOCIATED, OCCLUDING SURFACE CYCLONE WILL WEAKEN
ACROSS SOUTHERN MB BY THIS EVENING, AS A TRAILING COLD FRONT MOVES
ACROSS MN/IA/KS/MO AND NORTHERN OK. LOW-LEVEL MOISTURE WILL SPREAD
NORTHWARD ACROSS IA/MN IN ADVANCE OF THE COLD FRONT, BENEATH THE
NORTHEAST EDGE OF AN ELEVATED MIXED LAYER. SURFACE HEATING AND THE
DEGREE OF BUOYANCY MAY BE LIMITED BY EXTENSIVE CLOUDS FROM IA INTO
MN, AND FORECAST WIND PROFILES SHOW COMPLEX/MESSY HODOGRAPHS
STRUCTURES (STRONGER LOW-LEVEL SHEAR LINGERING ACROSS IA). MIXED
CONVECTIVE MODES ARE EXPECTED ALONG AND AHEAD OF THE FRONT THIS
AFTERNOON, WHICH COULD PRODUCE OCCASIONAL WIND DAMAGE, LARGE HAIL
AND PERHAPS A COUPLE OF TORNADOES.
THE MORE SUBSTANTIAL SEVERE THREAT IS EXPECTED LATE THIS AFTERNOON
THROUGH LATE EVENING FROM EASTERN KS INTO FAR NORTHERN OK, NEAR AND
JUST NORTHEAST OF A COLD FRONT/DRYLINE TRIPLE POINT AND WEAK
SECONDARY CYCLONE. A MIDLEVEL SPEED MAX NEAR THE FOUR CORNERS WILL
PROGRESS EASTWARD TO THE TX PANHANDLE BY THIS EVENING, WITH ASCENT
IN THE LEFT EXIT REGION OF THE JET COINCIDENT WITH THE TRIPLE POINT
NEAR OR JUST NORTH OF THE KS/OK BORDER. AN INFLUX OF MID 60S
BOUNDARY-LAYER DEWPOINTS BENEATH STEEP MIDLEVEL LAPSE RATES WILL
CONTRIBUTE TO MLCAPE OF 2000-3000 J/KG, WITH WEAKENING CONVECTIVE
INHIBITION ACROSS KS BY MID AFTERNOON.
STORM DEVELOPMENT IS EXPECTED ALONG THE COLD FRONT IN KS BY MID
AFTERNOON, WITH STORMS EXPECTED TO DEVELOP SOUTHWARD TO NEAR THE
TRIPLE POINT. THE LARGE BUOYANCY, STEEP MIDLEVEL LAPSE RATES AND
DEEP-LAYER SHEAR SUFFICIENT FOR SUPERCELLS WILL FAVOR VERY LARGE
HAIL (2-3 INCHES IN DIAMETER) WITH THE INITIAL/MORE DISCRETE STORMS.
THE TORNADO THREAT WILL PEAK THIS EVENING AS LOW-LEVEL
SHEAR/HODOGRAPH CURVATURE INCREASE NEAR THE KS/OK BORDER - THERE
WILL BE STRONG TORNADO POTENTIAL WITH THE ANCHOR/SOUTHERN SUPERCELLS
NEAR THE TRIPLE POINT. UPSCALE STORM GROWTH AND COLD POOL
DEVELOPMENT WILL FAVOR A MORE LINEAR CONVECTIVE MODE WITH OCCASIONAL
WIND DAMAGE AS THE OUTFLOW/EFFECTIVE COLD FRONT SPREADS
SOUTHEASTWARD INTO NORTHEAST OK AND SOUTHWEST MO OVERNIGHT.
..OK DRYLINE THIS EVENING
STORM DEVELOPMENT ALONG THE DRYLINE IN OK IS UNCERTAIN LATE THIS
AFTERNOON/EVENING. FORECAST SOUNDINGS SUGGEST THAT THE DEGREE OF
SURFACE HEATING/MIXING ALONG THE DRYLINE AND RESIDENCE TIME IN THE
DRYLINE CIRCULATION WILL BE CLOSE TO SUPPORTING DEEP CONVECTION. IF
STORMS DO FORM, THE ENVIRONMENT WILL CONDITIONALLY FAVOR VERY LARGE
HAIL INITIALLY, AND THE POSSIBILITY OF AN EVENING TORNADO THREAT
WITH ANY SUSTAINED STORM.
..THOMPSON/BENTLEY.. 04/23/2026
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