763
ACUS01 KWNS 230503
SWODY1
SPC AC 230502
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1202 AM CDT THU APR 23 2026
VALID 231200Z - 241200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN KANSAS...
..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.
...SOUTHERN AND CENTRAL PLAINS/LOWER TO MID MISSOURI VALLEY/UPPER
MISSISSIPPI VALLEY...
AN UPPER-LEVEL TROUGH WILL MOVE THROUGH THE CENTRAL ROCKIES THIS
MORNING, AND INTO THE HIGH PLAINS THIS AFTERNOON AS A 50 TO 60 KNOT
MID-LEVEL JET MOVES INTO THE GREAT PLAINS. AT THE SURFACE, A COLD
FRONT WILL ADVANCE SOUTHEASTWARD INTO THE MID MISSOURI VALLEY AND
CENTRAL PLAINS. MOISTURE ADVECTION AHEAD OF THE FRONT WILL INCREASE
SURFACE DEWPOINTS INTO THE MID 60S F BY AFTERNOON. THIS WILL
CONTRIBUTE TO MODERATE DESTABILIZATION AS SURFACE TEMPERATURES WARM
ALONG THE MOIST AXIS. THUNDERSTORMS ARE FIRST EXPECTED TO DEVELOP
AHEAD OF THE FRONT OVER THE MID MISSOURI AND UPPER MISSISSIPPI
VALLEYS IN THE EARLY TO MID AFTERNOON. CONVECTIVE COVERAGE WILL
RAPIDLY EXPAND SOUTHWARD INTO EASTERN KANSAS BY LATE AFTERNOON, AND
INTO FAR NORTHERN OKLAHOMA DURING THE EARLY TO MID EVENING. MCS
DEVELOPMENT APPEARS LIKELY TO TAKE PLACE ALONG AND AHEAD OF THE
FRONT.
THE BEST ENVIRONMENT FOR SEVERE STORMS WILL BE IN EASTERN KANSAS. IN
THIS AREA, RAP FORECAST SOUNDINGS LATE THIS AFTERNOON AHEAD OF THE
FRONT HAVE MLCAPE PEAKING JUST ABOVE 3000 J/KG, WITH 700-500 MB
LAPSE RATES IN THE 7.5 TO 8 C/KM RANGE. 0-6 KM SHEAR IS FORECAST TO
BE IN THE 35 TO 40 KNOT RANGE. THIS ENVIRONMENT WILL SUPPORT
SUPERCELLS WITH LARGE HAIL. HAILSTONES GREATER THAN 2 INCHES IN
DIAMETER WILL BE POSSIBLE WITH THE MORE INTENSE SUPERCELLS. IN
ADDITION, 0-3 KM STORM-RELATIVE HELICITY IS FORECAST TO INCREASE
INTO THE 300 TO 400 M2/S2 RANGE BY 00Z, AS AT 40 TO 50 KNOT
LOW-LEVEL JET STRENGTHENS. THIS WILL SUPPORT TORNADOES WITH
SUPERCELLS. SUPERCELLS WILL INITIALLY BE DISCRETE BUT A LINE IS
EXPECTED TO FORM BY EARLY EVENING. AS THE LINE FORMS, ROTATING CELLS
WITHIN THE LINE SHOULD ALSO BE CAPABLE OF PRODUCING TORNADOES. A
STRONG TORNADO OR TWO WILL BE POSSIBLE LATE THIS AFTERNOON AND EARLY
THIS EVENING. A WIND-DAMAGE THREAT IS ALSO EXPECTED TO DEVELOP. THE
SOUTHERN EDGE OF THE LINE WILL IMPACT FAR NORTHERN OKLAHOMA IN THE
EARLY TO MID EVENING. CONVECTIVE COVERAGE SHOULD BE ISOLATED FURTHER
SOUTH ACROSS THE REST OF OKLAHOMA.
FURTHER NORTH-NORTHEAST INTO IOWA AND SOUTHERN MINNESOTA,
INSTABILITY WILL NOT BE AS STRONG. RAP FORECAST SOUNDINGS BY LATE
AFTERNOON HAVE MLCAPE PEAKING IN THE 1500 TO 2000 J/KG RANGE. THIS,
COMBINED WITH 30 TO 35 KNOTS OF DEEP-LAYER SHEAR AND 700-500 MB
LAPSE RATES OF 7 TO 7.5 C/KM SHOULD SUPPORT LARGE HAIL WITH
SUPERCELLS. SUPERCELLS AND DEVELOPING LINE SEGMENTS SHOULD ALSO BE
CAPABLE OF PRODUCING WIND DAMAGE, HAIL AND A TORNADO OR TWO.
..BROYLES/CHALMERS.. 04/23/2026
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