802
ACUS03 KWNS 050730
SWODY3
SPC AC 050729
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0229 AM CDT TUE AUG 05 2025
VALID 071200Z - 081200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS AND NORTHERN ROCKIES...
..SUMMARY
THUNDERSTORMS WITH ISOLATED SEVERE GUSTS AND HAIL WILL BE POSSIBLE
ON THURSDAY FROM PARTS OF THE NORTHERN PLAINS WESTWARD INTO THE
NORTHERN ROCKIES.
..NORTHERN PLAINS
AT MID-LEVELS, A SHORTWAVE RIDGE IS FORECAST TO MOVE EASTWARD ACROSS
THE NORTHERN PLAINS ON THURSDAY, AS A SPEED MAX MOVES OVER THE TOP
OF THE RIDGE INTO SOUTHERN CANADA. AT THE SURFACE, A MOIST AND
UNSTABLE AIRMASS WILL BE IN PLACE ACROSS MOST OF THE NORTHERN
PLAINS. THE RIDGE WILL MOVE EASTWARD TOWARD THE UPPER MISSISSIPPI
VALLEY DURING THE DAY. IN ITS WAKE, ISOLATED CONVECTIVE DEVELOPMENT
IS EXPECTED DURING THE MID TO LATE AFTERNOON OVER THE WESTERN
DAKOTAS. THIS CONVECTION SHOULD REMAIN ELEVATED, DUE TO A SHALLOW
CAPPING INVERSION AROUND 750 MB THAT IS EVIDENT ON FORECAST
SOUNDINGS. DURING THE EARLY TO MID EVENING, SOME OF THE CONVECTION
COULD BECOME SURFACE-BASED AND BE ASSOCIATED WITH A POTENTIAL FOR
ISOLATED SEVERE GUSTS AND HAIL.
..NORTHERN ROCKIES
A MID-LEVEL TROUGH IS FORECAST TO MOVE ACROSS THE PACIFIC NORTHWEST
ON THURSDAY, AS FLOW REMAINS SOUTHWESTERLY AHEAD OF THE TROUGH OVER
THE NORTHERN ROCKIES. AT THE SURFACE, DEWPOINTS ARE FORECAST TO BE
FROM THE MID 40S TO LOWER 50S F THROUGHOUT MUCH OF THE REGION. AS
SURFACE TEMPERATURES WARM DURING THE DAY, SCATTERED THUNDERSTORMS
WILL LIKELY DEVELOP IN THE HIGHER TERRAIN, WITH MORE ISOLATED
CONVECTION EXPECTED ALONG AN AXIS OF INSTABILITY ACROSS CENTRAL
MONTANA. BY AFTERNOON, FORECAST SOUNDINGS ALONG THE AXIS OF
INSTABILITY HAVE WEAK INSTABILITY IN PLACE (MLCAPE AROUND 500 J/KG),
WITH 0-6 KM SHEAR MOSTLY IN THE 45 TO 55 KNOT RANGE. THIS, COMBINED
WITH STEEP LOW TO MID-LEVEL LAPSE RATES, SHOULD BE ENOUGH FOR AN
ISOLATED SEVERE THREAT. A FEW SEVERE WIND GUSTS AND HAIL WILL BE
POSSIBLE.
..BROYLES.. 08/05/2025
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