212
ACUS01 KWNS 311959
SWODY1
SPC AC 311957
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0257 PM CDT FRI JUL 31 2026
VALID 312000Z - 011200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE MIDDLE MISSISSIPPI VALLEY AND SOUTHERN HIGH PLAINS...
..SUMMARY
SEVERE THUNDERSTORMS ARE FORECAST THIS AFTERNOON AND EVENING ACROSS
THE MIDDLE MISSISSIPPI VALLEY AND OZARKS. ISOLATED TO WIDELY
SCATTERED SEVERE STORMS ARE ALSO POSSIBLE ACROSS THE
CENTRAL/SOUTHERN HIGH PLAINS INTO THE SOUTHERN PLAINS THIS AFTERNOON
THROUGH EARLY EVENING.
..20Z UPDATE
THE FORECAST REMAINS ON TRACK, AND ONLY MINOR ADJUSTMENTS WERE MADE
WITH THIS UPDATE. THE SLGT RISK IN THE MIDDLE MS VALLEY WAS EXPANDED
SOUTHWARD INTO NORTHERN ARKANSAS -- DRIVEN BY 15-PERCENT WIND
PROBABILITIES. HERE, TEMPERATURES HAVE WARMED INTO THE UPPER 80S TO
LOWER 90S AMID MIDDLE/UPPER 70S DEWPOINTS -- YIELDING
MODERATE-STRONG SURFACE-BASED BUOYANCY. HIGH-RESOLUTION GUIDANCE IS
IN GOOD AGREEMENT, DEPICTING A SOUTHEASTWARD-MOVING LINE OF STORMS
MOVING INTO THIS ENVIRONMENT TONIGHT. DESPITE A GRADUAL INCREASE IN
NOCTURNAL COOLING AND BOUNDARY-LAYER STATIC STABILITY, THE RICH
MOISTURE AND STRENGTHENING 30-KT WEST-SOUTHWESTERLY LLJ SHOULD
SUPPORT A CONTINUED RISK OF SCATTERED WIND DAMAGE INTO THE OVERNIGHT
HOURS.
FARTHER NORTH, THE MRGL RISK WAS TRIMMED IN PORTIONS OF IL, WHERE
LIMITED AIR MASS RECOVERY IN THE WAKE OF ONGOING CONVECTION WILL
TEMPER THE SEVERE RISK THIS AFTERNOON/EVENING.
..WEINMAN.. 07/31/2026
PREV DISCUSSION
/ISSUED 1128 AM CDT FRI JUL 31 2026/
..MIDDLE MISSISSIPPI VALLEY AND OZARKS
RECENT SURFACE ANALYSIS PLACES A LOW OVER THE CENTRAL MN/IA BORDER
VICINITY. A COLD FRONT EXTENDS SOUTHWESTWARD FROM THIS LOW INTO
SOUTHWEST KS BEFORE THEN ARCING MORE WESTWARD ACROSS THE OK
PANHANDLE AND NORTHWESTWARD THROUGH SOUTHEAST CO. A PRE-FRONTAL
TROUGH ALSO EXTENDS FROM THIS LOW TO ANOTHER WEAK LOW IN THE
SOUTH-CENTRAL KS/NORTH-CENTRAL OK BORDER VICINITY (ABOUT 25-30 MILES
NORTH OF ENID, OK), BEFORE CONTINUING SOUTHWESTWARD THROUGH THE TX
SOUTH PLAINS. SHOWERS AND THUNDERSTORMS ARE CURRENTLY ONGOING FROM
SOUTHWEST OK THROUGH SOUTHWEST MO AND SOUTHERN IL WITHIN THE WARM
CONVEYOR PRECEDING THESE SURFACE BOUNDARIES. EXTENSIVE CLOUD COVER
ASSOCIATED WITH THESE SHOWERS AND STORMS EXTENDS FROM OK INTO MO AND
IL AS WELL, WITH ADDITIONAL CLOUD COVER NEAR THE SURFACE LOW OVER
MUCH OF MN, IA, WI, AND IL.
SHELTERED ENVIRONMENT ACROSS THE WARM SECTOR BENEATH THIS CLOUD
COVER IS CHARACTERIZED BY DEWPOINTS IN THE LOW 70S. GENERAL
EXPECTATION IS FOR THIS AIRMASS TO DESTABILIZE AS THE ONGOING
SHOWERS AND THUNDERSTORM CONTINUE TO SHIFT EASTWARD/NORTHEASTWARD
AND SKIES CLEAR BEFORE THE ARRIVAL OF THE PRE-FRONTAL TROUGH AND
COLD FRONT. THE PRIMARY LOW WILL CONTINUE TO OCCLUDE, AND THE
DEVELOPMENT OF A SECONDARY TRIPLE POINT FARTHER SOUTH ACROSS
NORTHERN MO APPEARS LIKELY. AFTERNOON THUNDERSTORM DEVELOPMENT IS
ANTICIPATED ALONG THE COLD FRONT AND PRE-FRONTAL TROUGH AS WELL AS
NEAR THE SURFACE LOW AND TRIPLE POINT. EFFECTIVE DEEP-LAYER SHEAR
AROUND 30 TO 40 KT SHOULD BE SUFFICIENT FOR ORGANIZED STORM
STRUCTURES. A MORE CELLULAR MODE IS LIKELY EARLY IN THE CONVECTIVE
CYCLE, BEFORE TRENDS TOWARDS A MORE LINEAR/BOWING MODE OVER TIME AS
COLD POOLS AMALGAMATE. GIVEN THE OVERALL MOIST PROFILES,
WATER-LOADED DOWNBURSTS APPEAR TO BE THE PRIMARY RISK DURING THE
MORE INITIAL CELLULAR MODE BEFORE COLD-POOL DRIVEN GUSTS BECOME MORE
LIKELY DURING THE LINEAR PHASE. THE THREAT FOR DAMAGING WINDS SHOULD
SPREAD SOUTHEASTWARD REGIONALLY THROUGH LATE AFTERNOON AND EVENING.
A CORRIDOR OF MORE SOUTHERLY (PERHAPS EVEN SLIGHTLY SOUTHEASTERLY)
WIND IS ANTICIPATED SOUTH OF THIS TRIPLE POINT, COMBINING WITH LOW
TO MID LEVEL SOUTHWESTERLIES TO SUPPORT MODERATE LOW-LEVEL SHEAR AND
AN ASSOCIATED THREAT FOR BRIEF TORNADOES.
..FRONT RANGE/RATON MESA INTO THE TX PANHANDLE/SOUTH PLAINS
STORMS ARE EXPECTED TO DEVELOP AND INCREASE IN COVERAGE ACROSS THE
HIGH TERRAIN THROUGH MID/LATE AFTERNOON BEFORE THEN SUBSEQUENTLY
SPREADING SOUTHEASTWARD INTO THE VERY WARM AND DEEPLY MIXED BOUNDARY
LAYER ACROSS THE LOWER ELEVATIONS. HIGH-BASED, OUTFLOW-DOMINANT
STORM STRUCTURES COULD SUPPORT THE POTENTIAL FOR STRONG TO SEVERE
GUSTS. ADDITIONALLY, INTERACTION BETWEEN THESE STORMS (AND
ASSOCIATED OUTFLOW) AND THE SOUTHWARD PROGRESSING FRONT MAY OCCUR
FROM NORTHEAST NM INTO THE TX PANHANDLE/SOUTH PLAINS. THIS
INTERACTION COULD RESULT IN A CORRIDOR OF GREATER WIND GUST
POTENTIAL FROM EAST-CENTRAL NM INTO THE TX SOUTH PLAINS DURING THE
LATE AFTERNOON.
..WESTERN AR INTO SOUTHWEST OK/NORTHWEST TX
THUNDERSTORMS WILL LIKELY REDEVELOP ON SCATTERED BASIS ON THE FRONT
LATER THIS AFTERNOON AND EVENING. THE VERY WARM AND MOIST AFTERNOON
BOUNDARY LAYER WILL SUPPORT THE POTENTIAL FOR SEVERE CALIBER WIND
GUSTS REGIONALLY. DEEP-LAYER WIND PROFILES WILL GENERALLY BE WEAK,
BUT STRONGER MID/HIGH-LEVEL NORTHWESTERLIES COULD SUPPORT A DEGREE
OF STORM ORGANIZATION AS STORMS CLUSTER AND SPREAD
SOUTH-SOUTHEASTWARD.
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