775  
ACUS02 KWNS 151732  
SWODY2  
SPC AC 151731  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1231 PM CDT WED JUL 15 2026  
 
VALID 161200Z - 171200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF  
WESTERN MONTANA...  
   
..SUMMARY  
 
SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS PARTS OF WESTERN  
MONTANA, MAINLY THURSDAY AFTERNOON AND EVENING. LOCALLY DAMAGING  
WINDS MAY ALSO OCCUR ACROSS PARTS OF NORTHERN NEW ENGLAND.  
   
..PARTS OF WESTERN/CENTRAL MT...ID...NORTHWEST WY  
EASTERN  
OR/WA...  
A SEASONABLY STRONG MID/UPPER-LEVEL CYCLONE OFFSHORE OF THE PACIFIC  
NORTHWEST IS FORECAST TO MOVE TOWARD VANCOUVER ISLAND THROUGH THE  
PERIOD. THE GLANCING INFLUENCE OF THIS FEATURE, COMBINED WITH  
MONSOONAL MOISTURE AND DIURNAL HEATING ACROSS THE HIGHER TERRAIN,  
WILL AID IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS BY AFTERNOON  
ACROSS PARTS OF ID/MT AND ADJACENT PORTIONS OF EASTERN OR/WA.  
 
AT THIS TIME, THE GREATEST SEVERE POTENTIAL APPEARS TO BE ACROSS  
PARTS OF WESTERN MT, WHERE MODERATE BUOYANCY (MLCAPE OF NEAR/ABOVE  
1000 J/KG) AND VEERING WIND PROFILES (WITH 30+ KT OF EFFECTIVE SHEAR  
DESPITE MODEST MIDLEVEL FLOW) WILL SUPPORT DEVELOPMENT OF ORGANIZED  
MULTICELLS AND PERHAPS A COUPLE OF SUPERCELLS, WITH AN ATTENDANT  
THREAT OF HAIL AND LOCALIZED SEVERE GUSTS. 15% HAIL PROBABILITIES  
HAVE BEEN ADDED ACROSS THE AREA TO ACCOUNT FOR THIS POTENTIAL.  
 
INSTABILITY IS EXPECTED TO BE SOMEWHAT WEAKER ACROSS PARTS OF ID AND  
EASTERN OR/WA, BUT FAVORABLE DEEP-LAYER SHEAR MAY RESULT IN  
DEVELOPMENT OF ISOLATED STRONG TO SEVERE STORMS. SOME CLUSTERING MAY  
EVENTUALLY RESULT IN POCKETS OF LOCALLY INCREASED SEVERE-WIND  
POTENTIAL, ESPECIALLY WHERE STRONGER PRE-STORM HEATING AND  
STEEPENING OF LOW-LEVEL LAPSE RATES OCCURS.  
   
..PARTS OF NORTHERN NEW ENGLAND  
 
A VIGOROUS MID/UPPER-LEVEL SHORTWAVE TROUGH IS FORECAST TO MOVE  
ACROSS NORTHERN NEW ENGLAND THURSDAY AFTERNOON. VERTICALLY  
INTEGRATED SMOKE FORECASTS FROM THE HRRR SUGGEST THAT THE DENSEST  
SMOKE WILL LARGELY REMAIN SOUTH OF MAINE, WHICH WOULD ALLOW FOR  
DIURNAL STEEPENING OF LOW-LEVEL LAPSE RATES.  
 
WITH LIMITED LOW-LEVEL MOISTURE, BUOYANCY WILL LIKELY REMAIN WEAK TO  
NEGLIGIBLE FOR MUCH OF THE DAY. HOWEVER, STRONGLY FORCED LOW-TOPPED  
CONVECTION MAY DEVELOP IN ASSOCIATION WITH THE APPROACHING SHORTWAVE  
TROUGH AND ATTENDANT COLD FRONT, AND MOVE SOUTHEASTWARD THROUGH THE  
AFTERNOON. STRONG FLOW (50+ KT AT 700 MB) AND STEEP LOW-LEVEL LAPSE  
RATES WILL SUPPORT POTENTIAL FOR STRONG/DAMAGING GUSTS, POTENTIALLY  
AUGMENTED BY CONVECTIVE DOWNDRAFTS. 5% WIND PROBABILITIES HAVE BEEN  
INCLUDED TO ACCOUNT FOR THIS POTENTIAL.  
   
..MID-ATLANTIC VICINITY  
 
SIMILAR TO D1/WEDNESDAY, STORM POTENTIAL IS UNCERTAIN AND  
POTENTIALLY LIMITED THURSDAY ACROSS PARTS OF THE MID-ATLANTIC,  
DESPITE A RELATIVELY FAVORABLE ENVIRONMENT IN THE VICINITY OF A COLD  
FRONT. WEAK LARGE-SCALE ASCENT AND THE POTENTIAL IMPACT OF SMOKE ON  
DIURNAL HEATING/DESTABILIZATION WILL LIKELY LIMIT STORM COVERAGE,  
WITH HREF CALIBRATED THUNDER PROBABILITIES CURRENTLY ONLY 10-20%.  
SEVERE PROBABILITIES HAVE BEEN WITHHELD DUE TO UNCERTAINTY REGARDING  
STORM DEVELOPMENT/COVERAGE, BUT THIS AREA WILL CONTINUE TO BE  
MONITORED FOR ANY INCREASING SIGNAL OF STORM DEVELOPMENT WITHIN THE  
CONDITIONALLY FAVORABLE ENVIRONMENT.  
   
..ARIZONA  
 
SCATTERED THUNDERSTORMS ARE AGAIN EXPECTED ACROSS PARTS OF ARIZONA  
ON THURSDAY. SOME STORMS WILL LIKELY BE ACCOMPANIED BY STRONG GUSTS,  
THOUGH ORGANIZED SEVERE POTENTIAL APPEARS LIMITED, WITH ONLY VERY  
LIGHT MIDLEVEL FLOW CURRENTLY INDICATED BY MOST GUIDANCE. TRENDS  
WILL BE MONITORED FOR ANY INCREASE IN POTENTIAL FOR ORGANIZED  
CLUSTERING.  
   
..SOUTHWEST/SOUTH-CENTRAL TX  
 
MODESTLY ENHANCED LOW-LEVEL SHEAR/SRH MAY PERSIST INTO THURSDAY  
MORNING ACROSS SOUTHWEST/SOUTH-CENTRAL TX. HOWEVER, MOST GUIDANCE  
SUGGESTS THAT CONVECTION WILL TEND TO WEAKEN NEAR/AFTER 12Z. AS A  
RESULT, NO TORNADO PROBABILITIES HAVE BEEN INTRODUCED, THOUGH A  
BRIEF/WEAK TORNADO CANNOT BE RULED OUT NEAR THE BEGINNING OF THE  
FORECAST PERIOD.  
 
..DEAN.. 07/15/2026  
 
 
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