646
ACUS01 KWNS 301955
SWODY1
SPC AC 301953
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0253 PM CDT THU JUL 30 2026
VALID 302000Z - 311200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTH DAKOTA...NEBRASKA...AND NORTHERN KANSAS...
..SUMMARY
THUNDERSTORMS WITH SEVERE WIND GUSTS AND ISOLATED LARGE HAIL ARE
FORECAST THIS AFTERNOON AND EVENING ACROSS PARTS OF THE CENTRAL AND
NORTHERN PLAINS, BUT ESPECIALLY ACROSS PARTS OF SOUTH DAKOTA,
NEBRASKA, AND NORTH-CENTRAL KANSAS. ISOLATED SEVERE WIND GUSTS MAY
ALSO OCCUR ACROSS PARTS OF THE SOUTHEAST.
..20Z UPDATE
THE FORECAST REMAINS ON TRACK, AND ONLY MINOR CHANGES WERE MADE WITH
THIS UPDATE. THE EASTERN EDGE OF THE SLGT RISK WAS TRIMMED IN
PORTIONS OF EASTERN SD AND NORTHEASTERN NE. HERE, PERSISTENT
CONVECTION WITHIN A WEAK WARM-ADVECTION REGIME PRECEDING A REMNANT
MCV WILL LIMIT AIR MASS RECOVERY AND TEMPER THE OVERALL SEVERE RISK
THIS AFTERNOON. FARTHER WEST, A MINOR EXPANSION OF THE SLGT RISK WAS
MADE OVER SOUTHWESTERN SD AND WESTERN NE, WHERE AMPLE BOUNDARY-LAYER
HEATING/DESTABILIZATION OF A MOIST AIR MASS IS UNDERWAY ALONG/AHEAD
OF A WELL-DEFINED SURFACE TROUGH/WIND SHIFT. ANY THUNDERSTORMS THAT
DEVELOP AND TRACK SOUTHEASTWARD THROUGH THIS CORRIDOR WILL POSE A
RISK OF LARGE HAIL INITIALLY, WITH AN INCREASING RISK OF SEVERE WIND
GUSTS AS STORMS GROW UPSCALE.
FINALLY, THE SLGT RISK WAS EXPANDED SLIGHTLY SOUTHEASTWARD IN FAR
SOUTHEASTERN NE AND NORTHEASTERN KS. THE LATEST HIGH-RESOLUTION
GUIDANCE IS IN GOOD AGREEMENT, DEPICTING ONE OR MORE ORGANIZED LINE
SEGMENTS TRACKING SOUTHEASTWARD TONIGHT. DESPITE INCREASING
NOCTURNAL PBL COOLING/STABILIZATION AHEAD OF THIS ACTIVITY, A
STRENGTHENING 30-40-KT SOUTHERLY LLJ SHOULD HELP MAINTAIN A RISK OF
DAMAGING WIND GUSTS INTO OVERNIGHT HOURS.
FOR ADDITIONAL DETAILS ON THE SEVERE RISK THROUGH THE AFTERNOON, SEE
SEVERE THUNDERSTORM WATCH 533, AND MCDS 1803 AND 1804.
..WEINMAN.. 07/30/2026
PREV DISCUSSION
/ISSUED 1121 AM CDT THU JUL 30 2026/
..NORTHERN/CENTRAL PLAINS
SHOWERS AND THUNDERSTORMS ARE CURRENTLY ONGOING WITHIN A MODEST
WARM-AIR ADVECTION REGIME FROM CENTRAL SD INTO NORTHEAST NE. THESE
STORMS WILL LIKELY WEAKEN OVER THE NEXT FEW HOURS AS THE LOW TO
MID-LEVEL FLOW DECREASES. THIS SHOULD ALLOW FOR SUFFICIENT AIRMASS
RECOVERY/DESTABILIZATION BY THE LATE AFTERNOON ACROSS MUCH OF THE
REGION. RECENT SURFACE ANALYSIS DEPICTED 70S DEWPOINTS INTO FAR
SOUTH-CENTRAL NE, AS WELL AS POCKETS OF GREATER LOW-LEVEL MOISTURE
IN WESTERN SD AND AHEAD OF A COLD FRONT IN NORTHEAST ND. HEATING
WITHIN THIS MOIST ENVIRONMENT TO THE WEST OF THE ONGOING STORMS (AND
ASSOCIATED CLOUDINESS) IS EXPECTED TO RESULT IN A CORRIDOR OF STRONG
TO VERY STRONG BUOYANCY BY THIS AFTERNOON.
CURRENT SATELLITE IMAGERY SHOWS A SHORTWAVE TROUGH MOVING ACROSS
SOUTHEAST MT AND WY. EXPECTATION IS FOR THIS WAVE TO CONTINUE
EASTWARD, INTERACTING WITH THE DESTABILIZED AND BUOYANT AIRMASS
ACROSS THE NORTH/CENTRAL PLAINS TO SUPPORT THUNDERSTORM DEVELOPMENT.
INITIAL DEVELOPMENT APPEARS MOST LIKELY ACROSS WESTERN/CENTRAL SD
WHERE THE ASCENT ATTENDANT TO THIS SHORTWAVE TROUGH WILL BE
AUGMENTED BY MESOSCALE LIFT NEAR A SURFACE LOW CURRENTLY OVER
SOUTHWEST SD. A MORE CELLULAR MODE IS LIKELY EARLY IN THE CONVECTIVE
CYCLE, WITH A TREND TOWARDS A MORE CLUSTERED/LINEAR MODE THEREAFTER.
PRIMARY THREAT WILL BE STRONG GUSTS WITH SOME ISOLATED HAIL
POSSIBLE, PARTICULARLY EARLY DURING THE MORE CELLULAR MODE.
IN ADDITION TO THE LOW OVER SOUTHWEST SD, RECENT SURFACE ANALYSIS
PLACED ANOTHER LOW OVER NORTHWEST KS. WEAK TROUGHING BETWEEN THESE
LOWS, LIKELY SHARPENED BY BAROCLINICITY DRIVEN BY DIFFERENTIAL
HEATING, COULD ACT AS A FAVORABLE CORRIDOR FOR FORWARD PROPAGATION
IF A MORE COHERENT LINEAR STRUCTURE MATERIALIZES.
..EASTERN ND INTO NORTHERN MN
THUNDERSTORM DEVELOPMENT IS EXPECTED THIS AFTERNOON FROM EASTERN ND
INTO NORTHERN MN ALONG A SOUTHEASTWARD-PROGRESSING COLD FRONT
FORECAST TO MOVE THROUGH THE REGION. MODERATE BUOYANCY WILL PRECEDE
THIS FRONT, BUT VERTICAL SHEAR WILL BE MODEST, LIMITING STORM
ORGANIZATION AND DURATION. EVEN SO, BUOYANCY WILL BE STRONG ENOUGH
FOR OCCASIONAL DAMAGING GUSTS AND ISOLATED INSTANCES OF HAIL.
..NORTHERN/CENTRAL HIGH PLAINS
POCKETS OF MODERATE INSTABILITY MAY DEVELOP IN PARTS OF EASTERN
COLORADO, WESTERN KANSAS AND EASTERN MONTANA. ALTHOUGH LARGE-SCALE
ASCENT WILL BE WEAK IN THESE AREAS, TOPOGRAPHIC FORCING WILL AID
CONVECTIVE INITIATION. DURING THE MID/LATE AFTERNOON INTO EVENING,
ISOLATED TO SCATTERED STORMS WILL MOVE EAST-SOUTHEASTWARD INTO THE
LOWER ELEVATIONS, WITH LOCALIZED STRONG TO SEVERE WIND GUSTS AND
HAIL POSSIBLE. SLIGHTLY STRONGER VERTICAL SHEAR IS POSSIBLE ACROSS
NORTH-CENTRAL/NORTHEAST MT, WHERE A FEW MORE ORGANIZED STORMS ARE
POSSIBLE.
..CENTRAL GULF COAST INTO NORTHERN FL/SOUTHERN GA
A MODEST BAROCLINIC BOUNDARY EXTENDS FROM CENTRAL AL SOUTHEASTWARD
THROUGH SOUTHERN/SOUTHEAST GA. DEWPOINTS TO THE SOUTH OF THIS
BOUNDARY ARE IN THE 70S, WITH TEMPERATURES ALREADY IN THE UPPER
80S/LOW 90S. MODERATE TO STRONG BUOYANCY WILL CONTINUE TO BUILD
ACROSS THIS REGION SOUTH OF THE BOUNDARY, WITH LOW-LEVEL CONVERGENCE
CONTRIBUTING TO SCATTERED TO WIDESPREAD THUNDERSTORM DEVELOPMENT.
VERTICAL SHEAR WILL REMAIN WEAK, AND A LARGELY DISORGANIZED
MULTICELLULAR STORM MODE IS EXPECTED. EVEN SO, WATER LOADING WITHIN
SOME OF THE STRONGER STORMS THAT DEVELOP AND MATURE COULD RESULT IN
ISOLATED DAMAGING WIND GUSTS THROUGH LATE AFTERNOON/EARLY EVENING.
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