651
ACUS03 KWNS 101838
SWODY3
SPC AC 101837
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0137 PM CDT WED SEP 10 2025
VALID 121200Z - 131200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE FOUR
CORNERS REGION...
..SUMMARY
ISOLATED STRONG TO SEVERE STORMS CAPABLE OF ISOLATED LARGE HAIL AND
SEVERE WIND GUSTS ARE POSSIBLE ACROSS THE FOUR CORNERS REGION ON
FRIDAY. ADDITIONAL STORMS ARE POSSIBLE OVER THE NORTHERN PLAINS AND
UPPER MIDWEST FRIDAY MORNING AND FRIDAY NIGHT.
..SYNOPSIS
ON FRIDAY, A STRONG TROUGH WILL BEGIN ACROSS THE INTERMOUNTAIN WEST
WITH A TROUGH ACROSS THE PLAINS AND A TROUGH ALONG THE EAST COAST.
THE PATTERN WILL SHIFT SLOWLY EAST THROUGH THE DAY. AT THE SURFACE,
EXPANSIVE HIGH PRESSURE WILL LEAD TO FAIR WEATHER ACROSS MUCH OF THE
EASTERN CONUS WITH A WEAK LEE CYCLONE IN THE CENTRAL/NORTHERN
PLAINS.
..FOUR CORNERS REGION
RESIDUAL MOISTURE WITHIN THE SOUTHWEST AND CENTRAL ROCKIES WILL
RESULT IN 500 TO 1000 J/KG MLCAPE BY EARLY FRIDAY AFTERNOON ACROSS
PORTIONS OF THE SOUTHWEST AND INTO SOUTHEAST UTAH AND WESTERN
COLORADO. THIS INSTABILITY, COMBINED WITH WEAK HEIGHT FALLS AND
TERRAIN CIRCULATIONS WILL RESULT IN WIDESPREAD THUNDERSTORM ACTIVITY
FRIDAY AFTERNOON. MODERATE MID-LEVEL FLOW (40 TO 45 KNOTS) WILL
RESULT IN SUFFICIENT SPEED SHEAR FOR SOME ORGANIZED STORM POTENTIAL.
WHILE INSTABILITY WILL BE OVERALL WEAK, POCKETS OF GREATER
INSTABILITY/STRONGER STORMS MAY RESULT IN A FEW ISOLATED SUPERCELLS
WITH A THREAT FOR LARGE HAIL AND SEVERE WIND GUSTS.
..NORTHERN PLAINS
A CLUSTER OF STORMS MAY BE ONGOING AT THE BEGINNING OF THE PERIOD
ACROSS THE EASTERN DAKOTAS/WESTERN MINNESOTA. IF THIS OCCURS, SOME
MARGINAL WIND/HAIL THREAT COULD EXIST DURING THE MORNING BEFORE THE
LOW-LEVEL JET WEAKENS. HOWEVER, THERE IS CONSIDERABLE UNCERTAINTY AT
THIS TIME WHETHER ONGOING CONVECTION WILL BE IN PLACE FRIDAY
MORNING.
ADDITIONAL STORM COVERAGE UNCERTAINTY EXISTS FRIDAY NIGHT. MOST
GUIDANCE IS FAIRLY CONSISTENTLY SHOWING A 40 TO 50 KNOT LOW-LEVEL
JET ACROSS THE CENTRAL PLAINS. MODERATE INSTABILITY WILL EXIST
ACROSS SOUTHERN SOUTH DAKOTA AND IF ISENTROPIC ASCENT CAN REACH THIS
FAR NORTH, SOME ELEVATED STRONG TO ISOLATED SEVERE STORMS MAY BE
POSSIBLE FRIDAY NIGHT. HOWEVER, AT THIS TIME THERE IS CONSIDERABLE
UNCERTAINTY WHETHER THIS FRONTAL ZONE AND THE LOW-LEVEL JET WILL
OVERLAP. IN ADDITION, THE LOW-LEVEL JET REMAINS MOSTLY VEERED FRIDAY
NIGHT WHICH WILL RESULT IN RELATIVELY WEAK ISENTROPIC ASCENT.
THEREFORE, A CONDITIONAL ELEVATED HAIL THREAT MAY EXIST ACROSS SOUTH
DAKOTA FRIDAY NIGHT, BUT STORM COVERAGE REMAINS TOO UNCERTAIN AT
THIS TIME FOR PROBABILITIES.
..BENTLEY.. 09/10/2025
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