591
ACUS02 KWNS 020451
SWODY2
SPC AC 020450
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1150 PM CDT SAT AUG 01 2026
VALID 031200Z - 041200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
NORTH DAKOTA...NORTHWEST MINNESOTA...AND A SMALL PART OF NORTHEAST
SOUTH DAKOTA...
..SUMMARY
WIDELY SCATTERED TO SCATTERED SEVERE STORMS ARE EXPECTED ACROSS
EASTERN NORTH DAKOTA, NORTHWEST MINNESOTA, AND A SMALL PART OF
NORTHEAST SOUTH DAKOTA MONDAY AFTERNOON INTO EVENING. SEVERE WIND
GUSTS AND LARGE HAIL WILL BE THE PRIMARY HAZARDS. ISOLATED DAMAGING
WINDS ARE POSSIBLE FROM CENTRAL AND EASTERN SOUTH DAKOTA INTO
WESTERN NEBRASKA, IN PORTIONS OF THE MID-ATLANTIC INTO NEW ENGLAND,
AND SOUTHEAST ARIZONA.
..SYNOPSIS
A VIGOROUS SHORT-WAVE TROUGH AND ATTENDING MID/UPPER-LEVEL JET
STREAKS INITIALLY OVER THE NORTHERN ROCKIES MONDAY MORNING WILL
PROGRESS THROUGH THE NORTHERN PLAINS AND THE UPPER MS VALLEY. AT THE
SURFACE, AN AREA OF LOW PRESSURE IS EXPECTED TO WEAKEN WHILE
DEVELOPING FROM WESTERN SD INTO NORTHWEST ON, ALONG A COLD FRONT
ADVANCING THROUGH THE NORTHERN PLAINS AND UPPER MS VALLEY. THE
SOUTHERN EXTENSION OF THE FRONT WILL PUSH INTO THE CENTRAL HIGH
PLAINS, WHERE IT WILL LINK WITH A SECONDARY CYCLONE OVER EASTERN CO.
ELSEWHERE, AN AMPLIFIED SHORT-WAVE TROUGH WILL PROGRESS THROUGH THE
NORTHEAST WITH A PRECEDING BELT OF ENHANCED MID/UPPER-LEVEL WINDS
OVERSPREADING THAT REGION. THE ASSOCIATED SURFACE LOW IS EXPECTED TO
TRACK ALONG THE ST. LAWRENCE VALLEY, WHILE A TRAILING FRONT MOVES
THROUGH THE MID-ATLANTIC AND MUCH OF NEW ENGLAND.
..NORTHERN AND CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY
ELEVATED THUNDERSTORMS MAY BE ONGOING AT 12Z MONDAY FROM CENTRAL ND
INTO THE ND-MN RED RIVER VALLEY, WITHIN A ZONE OF WARM ADVECTION AND
MOISTURE TRANSPORT AT THE TERMINUS OF A LOW-LEVEL JET (LLJ). THE LLJ
WILL PERSIST THROUGH THE DAY, AIDING IN AIR MASS RECOVERY IN THE
WAKE OF THE EARLY-DAY STORMS. BY AFTERNOON, THE COMBINATION OF
DAYTIME HEATING, BOUNDARY-LAYER DEWPOINTS IN THE 60S, AND STEEP
LAPSE RATES IS EXPECTED TO YIELD A MODERATELY UNSTABLE, BUT CAPPED
PRE-FRONTAL AIR MASS WITH MLCAPE UP TO 1000-2000 J/KG.
RENEWED THUNDERSTORM DEVELOPMENT IS ANTICIPATED BY MID- TO LATE
AFTERNOON ALONG THE COLD FRONT AND ANY RESIDUAL OUTFLOW BOUNDARIES
IN EASTERN ND INTO NORTHWEST MN, WHERE STRONGER DYNAMIC FORCING FOR
ASCENT SHOULD ERODE THE CAP. VERTICALLY VEERING WIND PROFILES WITH
40-50+ KT EFFECTIVE BULK SHEAR WILL CONTRIBUTE TO ORGANIZED STORM
MODES, INCLUDING SUPERCELLS AND BOWING STRUCTURES CAPABLE OF LARGE
HAIL AND DAMAGING WINDS. THE PRESENCE OF A 30-40 KT LLJ WILL LEAD TO
SIZABLE, CLOCKWISE-CURVED HODOGRAPHS WITH 0-1 KM SRH OF 200-300
M2/S2 DURING THE EVENING. HOWEVER, THE OVERALL TORNADO THREAT
REMAINS UNCERTAIN AS FORECAST SOUNDINGS INDICATE CONTINUED CAPPING
WITHIN THE INFLOW AIR MASS, POOR LOW-LEVEL LAPSE RATES, AND ONLY A
SMALL AMOUNT OF 0-3 KM CAPE.
STORM DEVELOPMENT FARTHER SOUTH ALONG THE FRONT IN SD AND NE REMAINS
MORE UNCERTAIN DUE TO CAPPING CONCERNS. SHOULD STORMS DEVELOP, THE
ENVIRONMENT WOULD SUPPORT THE POTENTIAL FOR SEVERE WIND GUSTS AND
PERHAPS MARGINALLY SEVERE HAIL.
..NEW ENGLAND INTO THE MID-ATLANTIC
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE ONGOING MONDAY MORNING
ACROSS PORTIONS OF THE MID-ATLANTIC INTO NEW ENGLAND. ASSOCIATED
CLOUDS AND PRECIPITATION ARE LIKELY TO LINGER INTO AFTERNOON,
LIMITING AIR MASS DESTABILIZATION IN SOME AREAS. HOWEVER, WHERE
STRONGER HEATING CAN OCCUR, THE PRESENCE OF DEWPOINTS IN THE UPPER
60S TO LOW 70S WILL CONTRIBUTE TO POCKETS OF MODERATE INSTABILITY
WITH MLCAPE UP TO 1000-1500 J/KG.
AIDED BY FORCING FOR ASCENT ATTENDANT TO THE SHORT-WAVE TROUGH,
THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY
THROUGH THE AFTERNOON ALONG AND AHEAD OF THE FRONT, NAMELY IN AREAS
THAT EXPERIENCE GREATER AIR MASS DESTABILIZATION. STEEPENING
LOW-LEVEL LAPSE RATES AND THE PRESENCE OF 35-45 KT OF DEEP-LAYER
SHEAR MAY SUPPORT EMBEDDED BOWING SEGMENTS CAPABLE OF DAMAGING WIND
GUSTS.
..SOUTHEAST ARIZONA
WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING THE
AFTERNOON OVER THE GILA MOUNTAINS AS WELL AS ALONG FAVORED TERRAIN
NEARER TO THE INTERNATIONAL BORDER. A SUBSEQUENT MERGING OF THE
SEPARATE REGIMES APPEARS POSSIBLE BY LATE AFTERNOON INTO EVENING.
THE PRESENCE OF A DEEP, WELL-MIXED BOUNDARY LAYER WITH MLCAPE UP TO
1000-1500 J/KG SUGGESTS THE POTENTIAL FOR SEVERE WIND GUSTS,
ESPECIALLY IF SOME COLD POOL ORGANIZATION CAN OCCUR.
..MEAD.. 08/02/2026
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