336  
FNUS21 KWNS 251653  
FWDDY1  
 
DAY 1 FIRE WEATHER OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1152 AM CDT SAT JUL 25 2026  
 
VALID 251700Z - 261200Z  
 
...CRITICAL FIRE WEATHER AREA FOR SCATTERED DRY THUNDERSTORMS ACROSS  
CENTRAL/SOUTHERN MONTANA...  
...CRITICAL FIRE WEATHER AREA FOR MUCH OF THE PACIFIC NORTHWEST INTO  
THE NORTHERN ROCKIES...  
 
METEOROLOGICAL CONDITIONS AMID NUMEROUS WILDFIRES AND 90-95TH  
PERCENTILE ERCS ACROSS THE NORTHWESTERN U.S. WILL LEAD TO ANOTHER  
DAY OF EXPANSIVE, AND POTENTIALLY DANGEROUS, FIRE CONCERNS.  
 
A SCATTERED DRY THUNDERSTORM RISK WAS INTRODUCED ACROSS  
CENTRAL/SOUTHERN MONTANA WHERE A GREATER COVERAGE OF THUNDERSTORMS  
AND LIGHTNING IGNITIONS ARE POSSIBLE ATOP RECEPTIVE FUELS. FORECAST  
SOUNDINGS DEPICT A HOT AND WELL-MIXED ENVIRONMENT THIS AFTERNOON  
WITH DEEP INVERTED-V PROFILES, AMPLE MUCAPE, AND 25-35 KT LCL-EL  
WINDS, INDICATING THUNDERSTORMS WILL BE CAPABLE OF SEVERE  
WIND-POTENTIAL AND LESS PRECIPITATION EFFICIENCY (SEE THE DAY 1  
CONVECTIVE OUTLOOK). THE ISOLATED DRY THUNDERSTORM RISK AREA WAS  
EXPANDED INTO NORTHWESTERN SOUTH DAKOTA AND NORTHEASTERN WYOMING  
BASED ON THE LATEST OBSERVATIONS AND FORECAST GUIDANCE. LIGHTNING  
IGNITIONS ARE ALSO POSSIBLE OUTSIDE OF THE ISOLATED DRY THUNDERSTORM  
HIGHLIGHTS, ON THE PERIPHERY OF HEAVIER PRECIPITATION CORES WHERE  
FUELS ARE RECEPTIVE.  
 
DESPITE MODERATE RH RECOVERIES ACROSS PORTIONS OF THE PACIFIC  
NORTHWEST, VALUES ARE QUICKLY DECLINING AND WILL APPROACH CRITICAL  
THRESHOLDS (15% OR LESS) BY PEAK HEATING. SOUTHWESTERLY TO WESTERLY  
SUSTAINED SURFACE WINDS ARE EXPECTED TO EXCEED 20 MPH, PERHAPS  
APPROACHING 25 MPH IN TERRAIN-FAVORED AREAS. LOCALLY EXTREMELY  
CRITICAL CONDITIONS MAY BE POSSIBLE WHERE THESE STRONGER SUSTAINED  
WINDS OVERLAP CRITICALLY LOW RH, IN ADDITION TO WIND GUSTS OF 30-40  
MPH PARTICULARLY IN THE COLUMBIA BASIN AND WESTERN/CENTRAL MONTANA.  
THESE CONDITIONS WILL FURTHER EXACERBATE THE FIRE ENVIRONMENT,  
IMPACTING ANY NEW/ONGOING WILDFIRES AND CONTROL EFFORTS.  
 
..ELIZALDE-GARCIA.. 07/25/2026  
   
PREV DISCUSSION  
/ISSUED 1143 PM CDT FRI JUL 24 2026/  
   
..SYNOPSIS  
 
UPPER RIDGING WILL PREVAIL OVER THE WESTERN AND CENTRAL CONUS TODAY.  
A BELT OF STRONGER MID-LEVEL FLOW, ACCOMPANIED BY EMBEDDED MID-LEVEL  
IMPULSES, WILL TRAVERSE THE PERIPHERY OF THE UPPER RIDGE AND  
OVERSPREAD THE WEST COAST TOWARD THE NORTHERN ROCKIES. THIS BELT OF  
STRONGER FLOW ALOFT WILL SUPPORT DRY AND WINDY CONDITIONS SUPPORTIVE  
OF WILDFIRE SPREAD, WITH DEEP-LAYER ASCENT ASSOCIATED WITH EMBEDDED  
IMPULSES ALSO SUPPORTING DRY THUNDERSTORM INITIATION, ESPECIALLY  
OVER PORTIONS OF MONTANA.  
   
..PARTS OF THE NORTHERN SIERRA TO THE NORTHERN ROCKIES  
 
THROUGH THE AFTERNOON, A DRY BOUNDARY LAYER WILL MIX UPWARD TO THE  
MID-LEVELS, ALLOWING FOR DOWNWARD MOMENTUM TRANSPORT OF THE  
AFOREMENTIONED STRONGER MID-LEVEL FLOW ALOFT. BY AFTERNOON PEAK  
HEATING, SUSTAINED SOUTHWESTERLY SURFACE WINDS EXCEEDING 20 MPH  
SHOULD BECOME WIDESPREAD, ESPECIALLY IN TERRAIN FAVORING AREAS, FROM  
THE NORTHERN SIERRA TO THE NORTHERN ROCKIES. FIFTEEN PERCENT RH  
SHOULD BE COMMON BY AFTERNOON PEAK HEATING, OVERLAPPING WITH MANY  
AREAS EXPERIENCING 20+ MPH SUSTAINED WINDS, WARRANTING WIDESPREAD  
CRITICAL HIGHLIGHTS GIVEN DRY FUELS.  
   
..PORTIONS OF MONTANA  
 
GUIDANCE CONSENSUS (INCLUDING HIGH-RESOLUTION MEMBERS) DEPICTS AT  
LEAST SCATTERED THUNDERSTORM DEVELOPMENT ACROSS MUCH OF MONTANA BY  
AFTERNOON AS A MID-LEVEL IMPULSE OVERSPREADS THE REGION. FORECAST  
SOUNDINGS SHOW CLASSIC INVERTED-V PROFILES EXTENDING UP TO 500 MB,  
AMID APPRECIABLE FLOW ALOFT. AS SUCH, FAST-MOVING AND HIGH-BASED  
STORMS WILL PROMOTE DRY LIGHTNING STRIKES OVER FUEL BEDS RECEPTIVE  
TO FIRE SPREAD, WARRANTING ISOLATED DRY THUNDERSTORM HIGHLIGHTS.  
FURTHERMORE, STRONG VERTICAL WIND SHEAR WILL ACCOMPANY THE MID-LEVEL  
IMPULSE, AND GIVEN APPRECIABLE BUOYANCY ALOFT, SEVERAL OF THESE  
STORMS MAY PRODUCE STRONG TO SEVERE WIND GUSTS, WHICH MAY EXACERBATE  
ANY ONGOING FIRES OR HOLDOVERS. PLEASE SEE THE LATEST DAY 1  
CONVECTIVE OUTLOOK FOR MORE DETAILS ON THE SEVERE THUNDERSTORM  
THREAT.  
   
..PLEASE SEE WWW.SPC.NOAA.GOV/FIRE FOR GRAPHIC PRODUCT  
 
 
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