050  
ACUS02 KWNS 020449  
SWODY2  
SPC AC 020447  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1147 PM CDT WED OCT 01 2025  
 
VALID 031200Z - 041200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY AFTERNOON  
INTO FRIDAY EVENING ACROSS PARTS OF THE EASTERN GREAT BASIN AND  
ADJACENT NORTHERN ROCKIES...  
   
..SUMMARY
 
 
SCATTERED STRONG THUNDERSTORMS MAY IMPACT PARTS OF THE NORTHERN  
INTERMOUNTAIN REGION INTO NORTHERN ROCKIES, ACCOMPANIED BY AT LEAST  
SOME RISK FOR SEVERE WIND AND HAIL LATE FRIDAY AFTERNOON AND  
EVENING.  
   
..DISCUSSION
 
 
MODELS CONTINUE TO INDICATE THAT GENERALLY WEAKER, BUT MORE  
AMPLIFIED, FLOW WILL PREVAIL ACROSS THE SOUTHERN MID-LATITUDES OF  
THE EASTERN PACIFIC INTO WESTERN ATLANTIC THROUGH THIS PERIOD, WITH  
A STRONGER SOMEWHAT MORE PROGRESSIVE REGIME ACROSS THE NORTHERN  
MID-LATITUDES. WITHIN THIS REGIME, LARGE-SCALE MID-LEVEL RIDGING  
OFFSHORE OF THE NORTH AMERICAN PACIFIC COAST MAY CONTINUE TO BUILD  
THROUGH MUCH OF THE EASTERN PACIFIC, WHERE BOTH STREAMS MAY BECOME  
LARGELY IN PHASE. DOWNSTREAM, WHILE MID-LEVEL TROUGHING, WITH A  
COUPLE OF EMBEDDED SMALLER-SCALE PERTURBATIONS, MAY PROGRESS ACROSS  
THE CANADIAN ROCKIES INTO THE CANADIAN PRAIRIES, ANOTHER NOTABLE  
SHORT WAVE TROUGH IS FORECAST TO CONTINUE TO DIGGING ACROSS THE  
SIERRA NEVADA INTO THE GREAT BASIN FRIDAY THROUGH FRIDAY NIGHT.  
 
FARTHER EAST, BROAD SOUTHERN MID-LATITUDE MID-LEVEL RIDGING MAY  
SLOWLY SHIFT EASTWARD ACROSS THE OHIO VALLEY THROUGH MID ATLANTIC  
VICINITY, WHILE IN LOWER LATITUDES WEAK MID/UPPER TROUGHING LINGERS  
ACROSS THE GULF BASIN INTO SOUTHWESTERN ATLANTIC.  
 
BENEATH THIS REGIME, IT APPEARS THAT SURFACE RIDGING WILL BE  
MAINTAINED, BUT CONTINUE TO SLOWLY WEAKEN, FROM THE GULF COAST AND  
SOUTHERN GREAT PLAINS INTO THE MID-LATITUDE WESTERN ATLANTIC. WHILE  
SURFACE TROUGHING MAY MODESTLY DEEPEN ACROSS THE NORTHERN GREAT  
PLAINS INTO THE LEE OF THE FRONT RANGE, A SUBSTANTIVE RETURN FLOW OF  
LOW-LEVEL MOISTURE EMANATING FROM THE GULF BASIN WILL CONTINUE TO BE  
IMPEDED. EVEN SO, SOME CONTINUING GRADUAL INCREASE IN SURFACE DEW  
POINTS APPEARS POSSIBLE ALONG AND SOUTHEAST OF THE SURFACE  
TROUGHING, WHICH MAY CONTRIBUTE TO MODEST DIURNAL BOUNDARY-LAYER  
DESTABILIZATION BENEATH A NORTH-NORTHEASTWARD ADVECTING PLUME OF  
WARM AND CAPPING ELEVATED-MIXED LAYER AIR.  
   
..EASTERN GREAT BASIN AND ADJACENT NORTHERN ROCKIES
 
 
MID-LEVEL COOLING AND FORCING FOR ASCENT, DOWNSTREAM OF THE FAIRLY  
VIGOROUS SHORT WAVE TROUGH, ARE LIKELY TO CONTRIBUTE TO AT LEAST  
WEAK BOUNDARY-LAYER DESTABILIZATION IN A CORRIDOR AHEAD OF AN  
ASSOCIATED SURFACE COLD FRONT BY LATE FRIDAY AFTERNOON. IT APPEARS  
THAT THIS WILL COINCIDE WITH STRENGTHENING OF SOUTHWESTERLY  
MID-LEVEL FLOW (INCLUDING TO 50-60+ KT AROUND 500 MB), WHICH WILL  
CONTRIBUTE TO STRONG SHEAR SUPPORTIVE OF ORGANIZED CONVECTIVE  
DEVELOPMENT. THIS MAY INCLUDE A FEW SUPERCELL STRUCTURES POSING A  
RISK FOR SEVERE WIND AND HAIL, PARTICULARLY NEAR THE EXIT REGION OF  
THE MID-LEVEL JET SPREADING ACROSS PARTS OF SOUTHEASTERN IDAHO INTO  
SOUTHWESTERN MONTANA AND WESTERN WYOMING. FARTHER SOUTH, ACROSS  
PARTS OF EASTERN UTAH INTO WESTERN COLORADO, THERMODYNAMIC PROFILES,  
INCLUDING A WARMER AND MORE DEEPLY MIXED BOUNDARY-LAYER, MAY BE MORE  
CONDUCIVE TO PRIMARILY A SEVERE WIND THREAT INTO EARLY FRIDAY  
EVENING.  
 
..KERR.. 10/02/2025  
 

 
 
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