404
ACUS02 KWNS 201657
SWODY2
SPC AC 201655
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1155 AM CDT WED AUG 20 2025
VALID 211200Z - 221200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE DAKOTAS INTO MINNESOTA...
..SUMMARY
AN ISOLATED SEVERE THREAT IS EXPECTED TO DEVELOP THURSDAY INTO
THURSDAY NIGHT OVER PARTS OF THE DAKOTAS INTO MINNESOTA, WITH SEVERE
GUSTS AND HAIL POSSIBLE.
..NORTHERN PLAINS INTO MINNESOTA
AN UPPER SHORTWAVE TROUGH/CYCLONE WILL DEEPEN AND DEVELOP EAST
ACROSS THE CANADIAN PRAIRIES ON THURSDAY. THIS WILL RESULT IN
DAMPENING OF THE UPPER RIDGE/HEIGHT FALLS ACROSS THE NORTHERN PLAINS
VICINITY. EARLY IN THE DAY, A WEAK SHORTWAVE IMPULSE AND REMNANT
CONVECTION/CLOUD DEBRIS WILL MOVE ACROSS PORTIONS OF ND/MN.
MEANWHILE, A COLD FRONT WILL DEVELOP EAST/SOUTHEAST ACROSS THE
DAKOTAS INTO NORTHERN MN THROUGH EARLY FRIDAY.
A CORRIDOR OF RICH BOUNDARY LAYER MOISTURE WITH DEWPOINTS GENERALLY
IN THE MID 60S TO NEAR 70 F WILL BE IN PLACE AHEAD OF THE COLD
FRONT. HOWEVER, STRONGER FORCING FOR ASCENT WILL NOT ARRIVE UNTIL
LATER IN THE EVENING/OVERNIGHT. IT IS UNCLEAR HOW MUCH DIURNAL
CONVECTION MAY DEVELOP DUE TO WEAKER FORCING AND CAPPING. IF A STORM
CAN FORM AHEAD OF THE FRONT DURING THE AFTERNOON, A CORRIDOR OF
2000-3000 J/KG MLCAPE WILL BE IN PLACE AMID 30+ KT EFFECTIVE SHEAR.
STRONG GUSTS AND HAIL WOULD BE POSSIBLE WITH CELLULAR ACTIVITY
THROUGH EARLY EVENING.
MORE LIKELY, CONVECTION WILL DEVELOP DURING THE EVENING/NIGHTTIME
HOURS ACROSS PARTS OF THE REGION. INITIAL STORMS MAY DEVELOP IN THE
POST-FRONTAL UPSLOPE REGIME ACROSS EASTERN WY/WESTERN SD AND DEVELOP
EAST ACROSS SD OVERNIGHT. IT IS UNCLEAR HOW INTENSE THESE INITIAL
STORMS FURTHER WEST WILL BE, AND PROBABILITIES MAY NEED TO BE
EXPANDED WESTWARD IN SUBSEQUENT OUTLOOKS IF CONFIDENCE INCREASES.
ONCE STORMS INTERACT WITH BETTER MOISTURE/INSTABILITY FURTHER EAST,
ISOLATED SEVERE GUSTS OR MARGINAL HAIL WILL BE POSSIBLE.
..LEITMAN.. 08/20/2025
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