388
ACUS48 KWNS 070843
SWOD48
SPC AC 070841
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0341 AM CDT SUN JUN 07 2026
VALID 101200Z - 151200Z
..DISCUSSION
..DAY4/WEDNESDAY
A CONCENTRATED AREA OF POTENTIALLY SIGNIFICANT SEVERE WEATHER IS
EXPECTED WEDNESDAY AFTERNOON AND EVENING, CENTERED ACROSS PORTIONS
OF MINNESOTA, WISCONSIN, AND IOWA.
A NUMBER OF THE DETERMINISTIC MODELS HAVE TRENDED SLIGHTLY FASTER
WITH THE PROGRESSION OF A LEAD SHORT-WAVE TROUGH AND ASSOCIATED JET
STREAK THROUGH THE NORTHERN PLAINS INTO UPPER MS VALLEY. AT THE
SURFACE, LOW PRESSURE INITIALLY OVER EASTERN SD IS FORECAST TO
DEVELOP NORTHEAST ALONG A COLD FRONT MOVING FROM THE EASTERN DAKOTAS
INTO MN. THE TRAILING EXTENSION OF THE BOUNDARY IS EXPECTED TO MOVE
MORE SLOWLY INTO THE MID MO VALLEY BEFORE STALLING IN RESPONSE TO A
DEEPENING CYCLONE OVER THE CENTRAL HIGH PLAINS.
STEEP LAPSE RATES AND A VERY MOIST BOUNDARY LAYER WILL CONTRIBUTE TO
MODERATE TO STRONG INSTABILITY ACROSS THE WARM SECTOR, WITH INITIAL
STORMS POTENTIALLY DEVELOPING BY EARLY AFTERNOON FROM THE RED RIVER
VALLEY INTO CENTRAL MN. SUBSEQUENT STORMS ARE LIKELY TO DEVELOP
ACROSS SOUTHERN MN INTO IA AND NORTHERN MO BY MID TO LATE AFTERNOON.
THE MODELS INDICATE 40+ KT DEEP-LAYER SHEAR ACROSS THE WARM SECTOR,
SUPPORTIVE OF SUPERCELLS AND BOWING STRUCTURES, CAPABLE OF ALL
SEVERE-WEATHER HAZARDS. THE SEVERE-WEATHER THREAT IS EXPECTED TO
SPREAD EAST THROUGH THE UPPER MIDWEST DURING THE EVENING HOURS.
..DAY 5/THURSDAY
BOTH THE ENSEMBLE MEAN AND DETERMINISTIC MODELS INDICATE THE
DEVELOPMENT OF A PROMINENT MID-LEVEL LOW OVER MANITOBA OR NORTHWEST
ONTARIO, WITH A POTENT SHORT-WAVE TROUGH MOVING THROUGH THE BASE OF
THAT FEATURE FROM THE UPPER MS VALLEY THROUGH THE UPPER GREAT LAKES.
A BELT OF UNSEASONABLY STRONG MID-LEVEL WINDS WILL ATTEND THE
SHORT-WAVE TROUGH FROM THE CENTRAL PLAINS INTO UPPER GREAT LAKES. AT
THE SURFACE, ENSEMBLE MEMBER CLUSTERING AND THE DETERMINISTIC MODELS
INDICATE THE PRIMARY LOW PRESSURE OVER ONTARIO, WITH SOME SIGNAL FOR
A SECONDARY CYCLONE/FRONTAL WAVE DEVELOPING FROM THE MID MO VALLEY
INTO UPPER MIDWEST DURING THE DAY. THE ASSOCIATED SURFACE FRONT IS
FORECAST TO ADVANCE THROUGH THE UPPER MIDWEST INTO UPPER GREAT
LAKES, WITH THE TRAILING EXTENSION OF THE BOUNDARY MOVING INTO THE
MID MS VALLEY AND SOUTHERN PLAINS.
THE PRESENCE OF MODERATE TO STRONG INSTABILITY ACROSS THE
PRE-FRONTAL WARM SECTOR SUGGESTS THE POTENTIAL FOR SEVERE STORMS
FROM THE UPPER MIDWEST INTO SOUTHERN PLAINS. WITHIN THAT BROADER
ENVELOPE, A POTENTIALLY MORE CONCENTRATED AREA OF SEVERE WEATHER MAY
MATERIALIZE FROM PARTS OF THE UPPER MIDWEST INTO MID MS VALLEY
DURING THE AFTERNOON AND EVENING HOURS. THERE, THE MOST FAVORABLE
OVERLAP OF THE FORCING FOR ASCENT, SUFFICIENT VERTICAL SHEAR, AND
AMPLE INSTABILITY ARE EXPECTED TO RESIDE.
..DAY 6/FRIDAY
THE ENSEMBLES AND MAJORITY OF DETERMINISTIC MODELS INDICATE THE
DAY5/THURSDAY UPPER GREAT LAKES SHORT-WAVE TROUGH WILL LIFT
NORTHEAST INTO ONTARIO AND QUEBEC. AT THE SURFACE, THE MODELS
SUGGEST THAT A WEAKENING COLD FRONT WILL ADVANCE INTO THE NORTHEAST
AND THROUGH THE OH VALLEY. SOME SEVERE-WEATHER THREAT COULD DEVELOP
ALONG THE FRONT BY AFTERNOON; HOWEVER, THE MODELS SUGGEST THAT THE
BOUNDARY WILL BECOME INCREASINGLY DISPLACED FROM THE STRONGEST
MID-LEVEL WINDS AND ASSOCIATED VERTICAL SHEAR. ISOLATED SEVERE
STORMS ALSO APPEAR POSSIBLE IN THE VICINITY OF A DEEPENING LEE
CYCLONE OVER THE CENTRAL HIGH PLAINS.
..DAYS 7-8/SATURDAY AND SUNDAY
THE ENSEMBLE MEAN SOLUTIONS INDICATE SOME POTENTIAL FOR MID-LEVEL
TROUGHING TO DEVELOP FROM THE NORTHERN ROCKIES INTO NORTHERN PLAINS
NEXT WEEKEND, WHICH IS SUPPORTED BY A NUMBER OF THE DETERMINISTIC
MODELS. AT THE SURFACE, THERE ARE INDICATIONS THAT A FRONTAL SYSTEM
MAY STRETCH FROM THE UPPER MIDWEST OR GREAT LAKES INTO CENTRAL HIGH
PLAINS, WHERE SOME SEVERE-WEATHER THREAT COULD DEVELOP.
..MEAD.. 06/07/2026
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