140  
FXUS65 KFGZ 291837  
AFDFGZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE FLAGSTAFF AZ  
1137 AM MST WED JUL 29 2026  
   
SYNOPSIS
 
SHOWERS AND THUNDERSTORMS ARE STARTING TO DEVELOP  
OVER THE HIGHER TERRAIN DUE TO CLEAR SKIES AND DAYTIME HEATING. A  
COMPLEX OF THUNDERSTORMS IS ALSO MOVING THROUGH FAR NORTHWEST  
ARIZONA AND INTO UTAH, AND OUTFLOW FROM THIS COMPLEX MAY TRIGGER  
MORE SHOWERS AND THUNDERSTORMS IN NORTHWEST ARIZONA THIS  
AFTERNOON. THURSDAY AND THROUGH THE WEEKEND, SHOWER AND  
THUNDERSTORM COVERAGE WILL BE ISOLATED AND MAINLY CONTAINED TO THE  
HIGHER TERRAIN AS DAYTIME HIGH TEMPERATURES SOAR, LIKELY REACHING  
THE WARMEST READINGS SO FAR THIS YEAR.  
 

 
   
DISCUSSION
 
 
THE WEAK MCV IS CONTINUING TO MOVE NORTH-NORTHEASTWARD AND SHOWERS  
AND THUNDERSTORMS ARE PUSHING INTO UTAH. MOSTLY CLEAR SKIES ARE  
LEADING TO SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG THE HIGHER  
TERRAIN OF THE RIM, AND WE SHOULD START TO SEE SHOWERS AND  
THUNDERSTORMS OVER THE WHITE MOUNTAINS OVER THE NEXT COUPLE OF  
HOURS AS WELL. DECENT SOUTHERLY FLOW IS EXPECTED TO PUSH  
DEVELOPING SHOWERS AND THUNDERSTORMS NORTHWARD, WHICH MAY LIMIT  
THE THREAT FOR FLASH FLOODING FROM INDIVIDUAL STORMS, BUT ANY  
BACK-BUILDING STORMS, CAUSED BY OUTFLOW FROM THUNDERSTORMS  
PUSHING SOUTHWARD WILL CREATE LOCALIZED AREAS OF HIGHER RISK FOR  
FLASH FLOODING THROUGH THE AFTERNOON AND EARLY EVENING HOURS.  
SHOWER AND THUNDERSTORM ACTIVITY SHOULD SETTLE DOWN TONIGHT.  
 
FOR THURSDAY AND INTO THE WEEKEND, THE HIGH OVER NEW MEXICO IS  
EXPECTED TO MOVE WESTWARD AND STRENGTHEN, THIS SLOWLY INTRODUCES  
DRIER, MID-LEVEL AIR AND SUBSIDENCE, CAUSING THE MONSOON ACTIVITY  
WILL SLOW DOWN. WE DON'T EXPECT A TOTAL STOP, BUT IT WILL BE SLOW  
THROUGH THE WEEKEND. THE HIGH MAY RETURN TO A MORE FAVORABLE  
LOCATION BY NEXT WEEK, WITH EASTERLY STEERING FLOW RETURNING, BUT  
THIS OUTLOOK COULD CHANGE IN A WEEK AND WILL BE MONITORED. THE  
RELOCATION AND STRENGTHENING OF THE HIGH, WITH THE SLOW DOWN OF  
THE MONSOON, WILL CAUSE TEMPERATURES TO SOAR. THIS WILL CAUSE MANY  
LOCATIONS TO REACH THE WARMEST TEMPERATURES SO FAR THIS YEAR.  
EXTREME HEAT WARNINGS REMAIN IN EFFECT FOR THE GRAND CANYON,  
YAVAPAI AND NORTHERN GILA COUNTIES BELOW 4000 FT, AS WELL FOR  
MARBLE AND GLEN CANYON, INCLUDING THE CITY OF PAGE, AND OAK CREEK  
AND SYCAMORE CANYONS, INCLUDING THE CITY OF SEDONA.  
 

 
   
AVIATION...WEDNESDAY 29/18Z THROUGH THURSDAY 30/18Z
 
MAINLY VFR  
CONDITIONS, MVFR POSSIBLE NEAR HEAVIER SHOWERS/STORMS. SCATTERED  
SHOWERS/STORMS MAINLY NORTH OF A KPRC-KSEZ-KJTC LINE BETWEEN  
19Z-03Z. WINDS SW 5-15KTS DAYTIME, LIGHT AND VARIABLE OR TERRAIN  
DRIVEN OVERNIGHT. GUSTY ERRATIC WINDS UP TO 40KTS POSSIBLE NEAR  
STORMS.  
 
OUTLOOK...THURSDAY 30/18Z THROUGH SATURDAY 01/18Z...MAINLY VFR  
CONDITIONS. ISOLATED SHOWERS/STORMS EACH AFTERNOON WITH BEST  
CHANCES NEAR THE WHITE MOUNTAINS. WINDS SW 5-15KTS DAYTIME, LIGHT  
AND VARIABLE OR TERRAIN DRIVEN OVERNIGHT. GUSTY ERRATIC WINDS UP  
TO 40KTS POSSIBLE NEAR STORMS.  
 

 
   
FIRE WEATHER...THURSDAY AND FRIDAY
 
A DOWNTURN IN PRECIPITATION  
CHANCES BEGINS ON THURSDAY WITH BEST CHANCES BEING OVER THE RIM AND  
THE WHITE MOUNTAINS. TEMPERATURES WARM TO 5-10 DEGREES ABOVE  
AVERAGE. WINDS SW 5-15 MPH. MINIMUM RH VALUES 15-30% THURSDAY, 10-  
25% FRIDAY.  
 
SATURDAY THROUGH MONDAY...HOT WITH TEMPERATURES 10-15 DEGREES ABOVE  
AVERAGE. ONLY PRECIPITATION CHANCES ARE MAINLY CONFINED TO THE WHITE  
MOUNTAINS THIS WEEKEND, WITH A SLIGHT UPTICK IN MONSOON ACTIVITY  
OVER THE HIGHER TERRAIN STARTING MONDAY. WINDS WILL BE GENERALLY  
LIGHT AND VARIABLE AT 5 TO 15 MPH. MINIMUM RH VALUES 7-20% SATURDAY,  
8-25% SUNDAY, 10-30% MONDAY.  
 

 
   
FGZ WATCHES/WARNINGS/ADVISORIES
 
 
EXTREME HEAT WARNING FROM 10 AM MST /11 AM MDT/ FRIDAY TO 8 PM  
MST /9 PM MDT/ SUNDAY FOR AZZ005-018-037-038.  
 
EXTREME HEAT WARNING FROM 10 AM THURSDAY TO 8 PM MST SUNDAY FOR  
AZZ006.  
 

 
 

 
 
PUBLIC...SCHANK  
AVIATION...BERNHART  
FIRE WEATHER...BERNHART  
 
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT  
WEATHER.GOV/FLAGSTAFF  
 
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