499  
FNUS22 KWNS 200657  
FWDDY2  
 
DAY 2 FIRE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0157 AM CDT WED AUG 20 2025  
 
VALID 211200Z - 221200Z  
   
..SYNOPSIS
 
 
THE STRONG RIDGE OVER THE WESTERN US IS EXPECTED TO CONTINUE TO  
BREAK DOWN UNDER THE SHORTWAVE TROUGH PASSING THROUGH THE NORTHERN  
ROCKIES. THIS WILL SUPPORT CONTINUED ADVECTION OF MONSOON MOISTURE  
NORTHWARD INTO THE GREAT BASIN AND PARTS OF SOUTHERN CALIFORNIA. BY  
THURSDAY AFTERNOON, PWAT VALUES ARE LIKELY TO BE BETWEEN 0.5-0.8"  
WITH A DRY SUB-CLOUD LAYER AND STEEP LOW-LEVEL LAPSE RATES. DESPITE  
SLOWER STORM MOTIONS AND ISOLATED COVERAGE OVER UTAH AND PARTS OF  
NEVADA, LITTLE WETTING RAINFALL IS EXPECTED. THIS SHOULD SUPPORT  
ISOLATED DRY THUNDERSTORM POTENTIAL THE UNDER THE UPPER HIGH AND  
INTO PORTIONS OF EASTERN IDAHO AND WESTERN WYOMING. WITH DRY FUELS  
IN PLACE, SOME LIGHTNING IGNITIONS ARE POSSIBLE.  
 
IN ADDITION TO THE POTENTIAL FOR THUNDERSTORMS, VERY WARM AND  
UNSTABLE CONDITIONS ARE EXPECTED ON THE PERIPHERY OF THE DEEPER  
MONSOON MOISTURE SURGE OVER PARTS OF THE SOUTHERN GREAT BASIN AND  
SOUTHERN CALIFORNIA. STEEP MID-LEVEL LAPSE RATES AND MARGINAL  
BUOYANCY WILL SUPPORT UNSTABLE CONDITIONS OVER MUCH OF THE  
SOUTHWEST. THIS COULD SUPPORT PLUME DOMINATED FIRE GROWTH AND  
PYROCONVECTION NEAR LARGE ACTIVE FIRES, WITH LOCALIZED EXTREME FIRE  
BEHAVIOR POSSIBLE.  
 
..LYONS.. 08/20/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT
 
 

 
 
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