000
ACUS01 KWNS 260601
SWODY1
SPC AC 260559
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1259 AM CDT SUN JUL 26 2026
VALID 261200Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
UPPER MIDWEST AND GREAT LAKES SOUTHWESTWARD INTO NEBRASKA...
..SUMMARY
SEVERE THUNDERSTORMS CAPABLE OF LARGE TO VERY LARGE HAIL, DAMAGING
WINDS (POSSIBLY 75+ MPH), AND POTENTIALLY SOME TORNADO RISK ARE
POSSIBLE FROM THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES
SOUTHWESTWARD INTO PORTIONS OF NEBRASKA, MAINLY THIS AFTERNOON INTO
TONIGHT.
..PARTS OF THE UPPER MIDWEST/GREAT LAKES
AN UPPER RIDGE WILL REMAIN ANCHORED FROM THE SOUTHWEST INTO THE
CENTRAL ROCKIES AND HIGH PLAINS THROUGH THE PERIOD. SEASONABLY
STRONG NORTHWESTERLY FLOW ALOFT WILL OVERSPREAD A VERY WARM, MOIST,
AND UNSTABLE ENVIRONMENT FROM PARTS OF THE UPPER MIDWEST AND GREAT
LAKES INTO THE CENTRAL PLAINS. THIS WILL RESULT IN A CONDITIONALLY
FAVORABLE ENVIRONMENT ACROSS A BROAD REGION, THOUGH WITH GENERALLY
SUBTLE FORCING MECHANISMS, CONSIDERABLE UNCERTAINTY REMAINS
REGARDING STORM EVOLUTION THROUGH THE PERIOD.
ASIDE FROM ANY MCV INFLUENCE ON EARLY-DAY CONVECTION, THE MOST
LIKELY INITIATION ZONE FOR DIURNAL STORM DEVELOPMENT CURRENTLY
APPEARS TO BE FROM NORTHERN MN INTO WI, WHERE ONE OR MORE
LOW-AMPLITUDE MIDLEVEL VORTICITY MAXIMA MAY IMPINGE UPON THE
DESTABILIZING ENVIRONMENT. INITIAL SUPERCELL DEVELOPMENT WOULD BE
POSSIBLE IN THIS AREA, POSING A THREAT OF LARGE TO VERY LARGE HAIL,
LOCALIZED SEVERE GUSTS, AND POTENTIALLY SOME TORNADO RISK. UPSCALE
GROWTH INTO ONE OR MORE INTENSE SOUTHEASTWARD-MOVING CLUSTERS WITH
ATTENDANT SEVERE-WIND SWATHS WOULD THEN BE POSSIBLE WITH TIME.
HOWEVER, SOME GUIDANCE REMAINS RELATIVELY SPARSE WITH
AFTERNOON/EVENING DEVELOPMENT, RESULTING IN UNCERTAINTY REGARDING
COVERAGE AND FAVORED CORRIDORS OF POTENTIALLY SIGNIFICANT SEVERE
POTENTIAL. GREATER PROBABILITIES AND AN UPGRADE TO LEVEL-3/ENHANCED
RISK MAY EVENTUALLY BE NEEDED, DEPENDING ON HOW THE UNCERTAINTIES
ARE RESOLVED LATER TODAY.
..NE INTO ADJACENT PARTS OF SOUTHEAST SD AND WESTERN IA
A SOMEWHAT SEPARATE AREA OF POTENTIAL SEVERE-STORM DEVELOPMENT IS
EXPECTED FROM PARTS OF CENTRAL NE INTO SOUTHEAST SD. INITIATION IS
EXPECTED NEAR A WEAK SURFACE TROUGH AS TEMPERATURES WARM TO NEAR
ABOVE 100 F AND CINH IS REMOVED. MLCAPE OF NEAR/ABOVE 1500 J/KG AND
EFFECTIVE SHEAR OF 30-40 KT WILL FAVOR DEVELOPMENT OF A FEW
ORGANIZED CELLS AND/OR CLUSTERS. SEVERE GUSTS OF 60-80 MPH APPEAR TO
BE THE MOST LIKELY HAZARD WITHIN THE HOT/WELL-MIXED ENVIRONMENT.
ISOLATED HAIL MAY ALSO OCCUR WITH ANY SUPERCELL, DESPITE RATHER WARM
TEMPERATURES ALOFT.
..MID-ATLANTIC INTO THE CAROLINAS/GA/NORTH FL
A SEASONABLY DEEP UPPER TROUGH WILL PERSIST ACROSS MUCH OF THE
EASTERN CONUS TODAY. A MODEST INCREASE IN MIDLEVEL NORTHWESTERLY
FLOW IS EXPECTED WITH TIME FROM THE MID-ATLANTIC INTO THE CAROLINAS,
GA, AND NORTH FL.
RELATIVELY COOL CONDITIONS, WEAK LAPSE RATES, AND THE POTENTIAL
INFLUENCE OF SMOKE WILL TEMPER DESTABILIZATION ACROSS THE MID
ATLANTIC. HOWEVER, MLCAPE INCREASING TO NEAR 1000 J/KG AMID 25-35 KT
OF EFFECTIVE SHEAR MAY SUPPORT OCCASIONAL STORM ORGANIZATION, WITH A
PRIMARY THREAT OF LOCALLY DAMAGING WIND.
FARTHER SOUTH, STRONGER HEATING/DESTABILIZATION IS EXPECTED ACROSS
THE CAROLINAS INTO GA/FL. DEEP-LAYER FLOW/SHEAR WILL BE SOMEWHAT
WEAKER COMPARED TO AREAS FARTHER NORTH, BUT MAY STILL BE SUFFICIENT
FOR TRANSIENT STORM ORGANIZATION AND A LOCALIZED DAMAGING-WIND
THREAT.
..SOUTHERN MT/NORTHERN WY INTO THE BLACK HILLS
HIGH-BASED CONVECTION IS EXPECTED TO DEVELOP THIS AFTERNOON ALONG
THE NORTHERN PERIPHERY OF THE UPPER RIDGE, WITH THE GREATEST
RELATIVE COVERAGE EXPECTED ACROSS PARTS OF NORTHERN WY AND SOUTHERN
MT. BUOYANCY IS EXPECTED TO REMAIN WEAK, BUT INVERTED-V PROFILES
WILL SUPPORT A THREAT OF STRONG TO LOCALIZED SEVERE GUSTS AS STORMS
MOVE EASTWARD TOWARDS THE BLACK HILLS BEFORE WEAKENING THIS EVENING.
..DEAN/SQUITIERI.. 07/26/2026
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