490
ACUS01 KWNS 141236
SWODY1
SPC AC 141234
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0734 AM CDT THU AUG 14 2025
VALID 141300Z - 151200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA...
..SUMMARY
THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL AND SEVERE WIND GUSTS
MAY OCCUR THIS AFTERNOON INTO TONIGHT ACROSS PARTS OF THE
NORTHERN/CENTRAL PLAINS AND UPPER MISSISSIPPI VALLEY.
..NORTHERN/CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY
ONGOING ELEVATED THUNDERSTORMS ACROSS PARTS OF EASTERN SD THIS
MORNING ARE OCCURRING IN ASSOCIATION WITH A LOW-AMPLITUDE SHORTWAVE
TROUGH AND RELATED LOW-LEVEL WARM ADVECTION. THIS ACTIVITY HAS
REMAINED SUB-SEVERE THROUGH MUCH OF THE EARLY MORNING HOURS, BUT IT
COULD STILL POSE AN ISOLATED HAIL THREAT IN THE SHORT TERM GIVEN
WEAK MUCAPE AND SUFFICIENT DEEP-LAYER SHEAR. IT REMAINS UNCLEAR
WHETHER ADDITIONAL THUNDERSTORM DEVELOPMENT WILL OCCUR LATER THIS
AFTERNOON ACROSS PARTS OF SOUTHERN MN AND VICINITY AS THE SHORTWAVE
TROUGH CONTINUES EASTWARD ACROSS THE UPPER MS VALLEY. THE AIRMASS
ACROSS THIS AREA WILL GRADUALLY DESTABILIZE THROUGH THE DAY, BUT
CAPPING MAY TEND TO INHIBIT ADDITIONAL DEVELOPMENT. STILL, A
CONDITIONAL THREAT FOR ISOLATED SEVERE HAIL/WIND EXISTS IF ROBUST
THUNDERSTORMS CAN INITIATE, SO HAVE MAINTAINED THE MARGINAL RISK
ACROSS SOUTHERN MN FOR THIS POSSIBILITY.
THUNDERSTORMS ACROSS SOUTHERN MANITOBA THIS MORNING ARE EXPECTED TO
GENERALLY REMAIN ALONG/NORTH OF THE INTERNATIONAL BORDER AS THEY
CONTINUE EASTWARD INTO WESTERN ONTARIO. A FAIRLY STRONG
MID/UPPER-LEVEL TROUGH WILL PROGRESS EASTWARD TODAY ACROSS
SASKATCHEWAN/MANITOBA, WITH THE SOUTHERN FRINGE OF THIS PERTURBATION
GLANCING THE NORTHERN PLAINS LATER TODAY. ENHANCED WESTERLY
MID-LEVEL FLOW WILL OVERSPREAD ND AND NORTHERN MN LATE THIS
AFTERNOON THOUGH TONIGHT, WHILE A SURFACE COLD FRONT ADVANCES
EAST-SOUTHEASTWARD ACROSS THE NORTHERN PLAINS THROUGH THE PERIOD.
LOW-LEVEL MOISTURE WILL CONTINUE TO STREAM NORTHWARD AHEAD OF THE
FRONT, WITH EVAPOTRANSPIRATION ALSO AIDING SURFACE DEWPOINTS
POTENTIALLY REACHING INTO THE UPPER 60S TO PERHAPS LOW 70S BY EARLY
EVENING. AMPLE DAYTIME HEATING AND STEEP LAPSE RATES ALOFT WILL AID
IN THE DEVELOPMENT OF AT LEAST 2500-3500 J/KG OF MLCAPE BY LATE
AFTERNOON.
THE PRIMARY UNCERTAINTY REGARDING CONVECTIVE DEVELOPMENT ALONG THE
FRONT IS A CAPPED 850-700 MB LAYER AND WEAK FORCING WITH SOUTHWARD
EXTENT ACROSS THE NORTHERN PLAINS, AS THE PRIMARY UPPER TROUGH WILL
REMAIN ACROSS CANADA THROUGH THE PERIOD. EVEN SO, LOW-LEVEL
CONVERGENCE ALONG THE FRONT MAY BECOME SUFFICIENT FOR CELLS TO
INITIATE BY EARLY EVENING, MAINLY ACROSS PARTS OF EASTERN ND INTO
NORTHWEST MN WHERE MLCIN SHOULD BE WEAKEST. ANY CONVECTION WHICH CAN
BE SUSTAINED COULD POSE A THREAT FOR LARGE TO ISOLATED VERY LARGE
HAIL GIVEN A FAVORABLE THERMODYNAMIC AND KINEMATIC ENVIRONMENT. SOME
POTENTIAL FOR UPSCALE GROWTH INTO CLUSTERS ALONG THE FRONT REMAINS
APPARENT THIS EVENING INTO THE EARLY OVERNIGHT HOURS, WITH GREATER
SEVERE WIND THREAT. HOWEVER, INHIBITION WILL QUICKLY INCREASE WITH
EASTWARD EXTENT ACROSS MN AS NOCTURNAL COOLING OF THE BOUNDARY LAYER
OCCURS; SO, THE SEVERE WIND THREAT REMAINS UNCERTAIN.
FINALLY, SCATTERED HIGH-BASED THUNDERSTORMS SHOULD OCCUR THIS
AFTERNOON AND EVENING FARTHER SOUTH ACROSS PARTS OF THE CENTRAL HIGH
PLAINS. AS THIS CONVECTION SPREADS EASTWARD AND ENCOUNTERS GREATER
INSTABILITY ALONG/EAST OF A SURFACE LEE TROUGH, IT MAY BECOME
CAPABLE OF PRODUCING ISOLATED SEVERE GUSTS AND PERHAPS MARGINALLY
SEVERE HAIL. THE LACK OF STRONGER FORCING ALOFT AND MODEST
DEEP-LAYER SHEAR SHOULD TEMPER THE OVERALL SEVERE THREAT WITH
SOUTHWARD EXTENT.
..GLEASON/LEITMAN.. 08/14/2025
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