865  
ACUS01 KWNS 290557  
SWODY1  
SPC AC 290556  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1256 AM CDT MON SEP 29 2025  
 
VALID 291200Z - 301200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
SEVERE THUNDERSTORM POTENTIAL IS LOW TODAY AND TONIGHT.  
   
..SYNOPSIS  
 
A SLUGGISH UPPER-LEVEL PATTERN WILL BE PRESENT ACROSS MUCH OF THE  
CONUS AS STRONG RIDGING CONTINUES TO BUILD OVER THE CENTRAL AND  
EASTERN PARTS OF THE COUNTRY. EAST OF THE RIDGE, TS IMELDA IS  
FORECAST TO GRADUALLY STRENGTHEN AS IT APPROACHES THE SOUTHEASTERN  
COAST. ACROSS THE WEST, THE REMNANTS OF AN UPPER LOW WILL TRANSITION  
TO A WEAK OPEN TROUGH AS A SECOND ELONGATED UPPER TROUGH LEISURELY  
MOVES ONSHORE ACROSS THE PACIFIC NORTHWEST.  
   
..NORTHERN GREAT BASIN AND ROCKY MOUNTAINS  
 
AHEAD OF THE WEAKENING UPPER LOW, STRONG HEATING OF A MODESTLY MOIST  
AIR MASS, IN COMBINATION WITH WEAK LARGE-SCALE ASCENT SHOULD FOSTER  
SCATTERED THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN ROCKIES.  
MODEST BUOYANCY FROM DIMINISHED MID-LEVEL LAPSE RATES AMID WEAKENING  
UPPER FLOW SUGGEST LITTLE STORM ORGANIZATION AND SEVERE POTENTIAL.  
 
FARTHER NORTH INTO NV/ID AND SOUTHERN MT, SCATTERED STORMS ARE  
EXPECTED ALONG AN EASTWARD-MOVING COLD FRONT THIS AFTERNOON AND  
EVENING. MODERATELY STRONG MERIDIONAL FLOW SHOULD OVERSPREAD THE  
WESTERN GREAT BASIN AHEAD OF THE DEEPENING WESTERN US TROUGH. AN  
OCCASIONAL STRONGER STORM IS POSSIBLE ALONG THE FRONT CAPABLE OF  
SPORADIC STRONG WIND GUSTS THIS AFTERNOON. HOWEVER, WITH ONLY MODEST  
SURFACE MOISTURE (DEWPOINTS IN THE 40S F) AND THUS LIMITED  
INSTABILITY (MLCAPE ~500 J/KG), WIDESPREAD SEVERE STORMS ARE NOT  
ANTICIPATED.  
   
..EASTERN FL PENINSULA TO COASTAL GA AND SC  
 
OUTER RAINBANDS ASSOCIATED WITH TROPICAL STORM IMELDA (CENTERED NEAR  
25.0N 77.1W) WILL APPROACH THE EASTERN FL PENINSULA AND SOUTHEAST  
ATLANTIC COAST LATE IN THE PERIOD. WHILE SOME STRONGER CONVECTION  
MAY APPROACH THE COAST LATE TONIGHT, CURRENT FORECAST TRAJECTORIES  
SUGGEST THAT MORE SUBSTANTIAL BUOYANCY/SHEAR PROFILES WITHIN THESE  
BANDS SHOULD REMAIN WELL OFFSHORE. AS SUCH, NO SEVERE PROBABILITIES  
HAVE BEEN INTRODUCED THIS OUTLOOK. SEE NHC.NOAA.GOV FOR THE LATEST  
TRACK INFORMATION.  
 
..LYONS/MOORE.. 09/29/2025  
 
 
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