890
ACUS02 KWNS 141733
SWODY2
SPC AC 141731
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1231 PM CDT THU AUG 14 2025
VALID 151200Z - 161200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL
WISCONSIN AND FAR EASTERN MINNESOTA...
..SUMMARY
SCATTERED SEVERE STORMS ARE LIKELY OVER PARTS OF THE NORTHERN PLAINS
AND UPPER MISSISSIPPI VALLEY ON FRIDAY.
..SYNOPSIS
A BELT OF STRONGER MID-LEVEL FLOW WILL BE PRESENT ACROSS THE
NORTHERN PLAINS ON FRIDAY ALONG THE NORTHERN PERIPHERY OF A BROAD
MID-LEVEL RIDGE. WITHIN THIS FLOW, A WEAK MID-LEVEL SHORTWAVE TROUGH
(PERHAPS AMPLIFIED BY DAY1/THURSDAY CONVECTION ACROSS THE CENTRAL
ROCKIES) WILL MOVE ACROSS THE NORTHERN PLAINS AND INTO THE UPPER
MIDWEST. THIS FEATURE MAY BE A FOCUS FOR SEVERE STORMS ON FRIDAY
AFTERNOON/EVENING. ANOTHER WEAK MID-LEVEL SHORTWAVE TROUGH IS
FORECAST TO TRAVERSE THE CENTRAL ROCKIES WITH ASSOCIATED ASCENT
OVERSPREADING THE CENTRAL/NORTHERN HIGH PLAINS. AT THE SURFACE, WEAK
LEE TROUGHING WILL BE PRESENT ACROSS THE CENTRAL/NORTHERN HIGH
PLAINS WITH A FRONT EXTENDING NORTHEAST ACROSS THE NORTHERN PLAINS
AND INTO THE UPPER MIDWEST.
..UPPER MIDWEST
MODERATE TO STRONG INSTABILITY IS FORECAST TO DEVELOP SOUTH OF A
STATIONARY FRONT ACROSS THE UPPER MIDWEST FRIDAY AFTERNOON. THE
COMBINATION OF ASCENT ASSOCIATED WITH A PASSING WEAK MID-LEVEL
SHORTWAVE TROUGH AND STRENGTHENING ISENTROPIC ASCENT AS THE
LOW-LEVEL JET STRENGTHENS, MAY PROVIDE AMPLE LIFT FOR SCATTERED
THUNDERSTORMS FRIDAY AFTERNOON/EVENING. SEVERAL CAMS ARE IN
RELATIVELY GOOD AGREEMENT FOR CONVECTIVE INITIATION ACROSS EASTERN
MINNESOTA WITH THE POTENTIAL FOR UPSCALE GROWTH INTO A MCS ACROSS
WISCONSIN LATE FRIDAY EVENING. HAVE INTRODUCED A SLIGHT RISK ACROSS
THIS REGION FOR AN INITIAL LARGE HAIL THREAT, FOLLOWED BY AN
INCREASING SEVERE WIND THREAT IF STORMS GROW UPSCALE. HOWEVER, THIS
AREA MAY NEED TO BE MOVED OR ENLARGED IN LATER OUTLOOKS DUE TO THE
INHERENT LACK OF PREDICTABILITY WITHIN A LOW-AMPLITUDE PATTERN. SOME
OF THIS UNPREDICTABILITY CAN BE SEEN BY RELATIVE OUTLIERS (HRRR AND
MPAS) WHICH SEEMS TO STEM FROM DIFFERENCE IN CONVECTIVE EVOLUTION ON
DAY 1/THURSDAY ACROSS THE CENTRAL ROCKIES AND ADJACENT PLAINS
TONIGHT.
..CENTRAL/NORTHERN HIGH PLAINS INTO THE NORTHERN PLAINS
ANOTHER WEAK MID-LEVEL SHORTWAVE TROUGH IS EXPECTED TO TRAVERSE THE
ROCKIES ON FRIDAY AND EVENTUALLY OVERSPREAD THE NORTHERN PLAINS BY
FRIDAY EVENING. MODERATE TO STRONG INSTABILITY AND MODERATE SHEAR
ALONG THE SOUTHERN PERIPHERY OF THE STRONGER MID-LEVEL WESTERLIES
MAY RESULT SEVERE STORMS. LARGE HAIL WOULD BE POSSIBLE IN THE
INITIAL, CELLULAR STAGES (ISOLATED SEVERE WIND ACROSS THE NE
PANHANDLE WHERE A HOT/WELL-MIXED ENVIRONMENT WILL BE PRESENT),
BEFORE AN INCREASING SEVERE WIND THREAT MAY DEVELOP BY LATER IN THE
EVENING ACROSS SOUTH DAKOTA. IF THIS MCS CAN MAINTAIN ITSELF FAR
ENOUGH EAST DURING THE EVENING, THE STRENGTHENING LOW-LEVEL JET
ACROSS CENTRAL AND EASTERN SOUTH DAKOTA COULD MAINTAIN THIS MCS WITH
SOME ISOLATED SEVERE WIND THREAT INTO THE EARLY MORNING HOURS ON
SATURDAY ACROSS EASTERN SOUTH DAKOTA AND PERHAPS FAR WESTERN
MINNESOTA AND NORTHWEST IOWA.
..BENTLEY.. 08/14/2025
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