003  
FNUS21 KWNS 161700  
FWDDY1  
 
DAY 1 FIRE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1159 AM CDT MON JUN 16 2025  
 
VALID 161700Z - 171200Z  
 
...CRITICAL FIRE WEATHER AREA FOR PARTS OF SOUTHERN  
NEVADA...SOUTHWESTERN UTAH AND NORTHWESTERN ARIZONA...  
   
..GREAT BASIN AND SOUTHWEST  
 
CURRENT SURFACE OBSERVATIONS SHOW SINGLE DIGIT RELATIVE HUMIDITY  
ACROSS THE SOUTHERN GREAT BASIN AND PARTS OF THE SOUTHWEST.  
INCREASING MID-LEVEL FLOW AHEAD OF AN UPPER-LEVEL TROUGH COUPLED  
WITH A VERY DRY/WELL-MIXED BOUNDARY LAYER WILL PROMOTE SUSTAINED  
SURFACE WINDS OF 20-25 MPH ACROSS A CORRIDOR FROM SOUTHERN NEVADA,  
NORTHWESTERN ARIZONA AND MUCH OF SOUTHERN UTAH WITH CRITICAL  
HIGHLIGHTS MAINTAINED AMID THE VERY LOW RELATIVE HUMIDITY REGIME AND  
DRY FUELS. ELEVATED FIRE WEATHER CONCERNS CONTINUE FOR A BROADER  
AREA OF THE GREAT BASIN AND SOUTHWEST AS THE UPPER-LEVEL TROUGH  
TRANSLATES EASTWARD THROUGH THE REGION. OTHERWISE, FORECAST REMAINS  
LARGELY ON TRACK.  
 
..WILLIAMS.. 06/16/2025  
   
PREV DISCUSSION  
/ISSUED 0158 AM CDT MON JUN 16 2025/  
   
..SYNOPSIS  
 
A MIDLEVEL TROUGH WILL ADVANCE EASTWARD FROM THE WEST COAST ACROSS  
PARTS OF THE GREAT BASIN/INTERMOUNTAIN WEST TODAY. WITHIN THE BASE  
OF THE TROUGH, MODERATE DEEP-LAYER WESTERLY FLOW WILL OVERSPREAD THE  
GREAT BASIN, WHILE A WEAK SURFACE LOW/TROUGH EVOLVES OVER THE LOWER  
CO RIVER VALLEY.  
   
..SOUTHERN NV INTO SOUTHWEST UT AND FAR NORTHWEST AZ  
 
ALONG THE SOUTHERN PERIPHERY OF MID/HIGH-LEVEL CLOUDS PRECEDING THE  
MIDLEVEL TROUGH, STRONG DIURNAL HEATING OF A WARM/DRY ANTECEDENT AIR  
MASS WILL RESULT IN A DEEPLY MIXED BOUNDARY LAYER ACROSS THE  
SOUTHERN GREAT BASIN. THE DEEP MIXING INTO THE ENHANCED FLOW ALOFT,  
ALONG WITH A TIGHTENING PRESSURE GRADIENT PERIPHERAL TO THE SURFACE  
LOW/TROUGH, WILL YIELD SINGLE-DIGIT RH AND 20-25 MPH SUSTAINED  
SOUTHWESTERLY SURFACE WINDS (WITH HIGHER GUSTS) ACROSS SOUTHERN NV,  
SOUTHWEST UT, AND FAR NORTHWEST AZ. GIVEN INCREASINGLY DRY FUELS  
ACROSS THE REGION, CRITICAL FIRE-WEATHER CONDITIONS ARE EXPECTED.  
 
FARTHER NORTH, MODEST WESTERLY FLOW ALOFT ACROSS THE CASCADES WILL  
CONTRIBUTE TO LOCALLY DRY/BREEZY DOWNSLOPE FLOW INTO THE COLUMBIA  
BASIN, WHERE ELEVATED FIRE-WEATHER CONDITIONS ARE FORECAST.  
   
..PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT  
 
 
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