630  
FXUS65 KFGZ 042346  
AFDFGZ  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE FLAGSTAFF AZ  
446 PM MST SUN MAY 4 2025  
   
SYNOPSIS  
A LARGE AREA OF LOW PRESSURE WILL BRING COOLER  
TEMPERATURES AND INCREASED CHANCES FOR PRECIPITATION TODAY THROUGH  
WEDNESDAY. WARM AND DRY WEATHER FORECAST TO RETURN THURSDAY ONWARD.  
 
 
   
DISCUSSION  
A DEEP AND COLD UPPER LOW (FOR MAY) IS NOW NEAR  
IMPERIAL AND WILL MOVE EASTWARD TODAY AND TONIGHT, BEFORE SLOWING  
DOWN AND SPLITTING ON MONDAY. THE LOW THEN RECONSOLIDATES NEAR THE  
FOUR CORNERS MONDAY NIGHT AND TUESDAY, WHILE FILLING AND WARMING. A  
TRAILING LOW MOVES INTO THE TROUGH POSITION OVER ARIZONA ON  
WEDNESDAY.  
 
THIS IS A COMPLICATED PATTERN, WITH MANY DIFFERENT ASPECTS TO LOOK  
AT. CONVECTION AHEAD OF THE LOW TODAY IS PRODUCING A FEW STRONGER  
THUNDERSTORMS, WHILE PRECIPITATION TONIGHT MAY ENHANCE ALONG A COLD  
FRONT. THEN, WRAPAROUND PRECIPITATION AFFECTS THE AREA MONDAY AND  
MONDAY NIGHT, WITH CONVECTIVE ELEMENTS CONTINUING INTO TUESDAY. THE  
TRAILING LOW WILL MOVE INTO A MOIST AIR MASS WEDNESDAY, WITH MORE  
POTENTIALLY SIGNIFICANT CONVECTION BREAKING OUT.  
 
ADDITIONALLY, WE WILL HAVE GUSTY PRE-FRONTAL WINDS TODAY, BUT OUR  
RELATIVE HUMIDITY LEVELS AND WIND SPEEDS AVOIDS THE NEED FOR ANY  
HEADLINES. SNOW LEVELS IN THE CORE OF THE LOW LATER TONIGHT AND  
MONDAY WILL PRODUCE AREAS OF SNOW ABOVE 6500-7500 FEET, WITH A FEW  
BRIEF TROUBLE SPOTS POSSIBLE FROM FLAGSTAFF WESTWARD.  
 
WHEN THIS IS ALL SAID AND DONE, MANY AREAS THROUGH WESTERN AND  
CENTRAL ARIZONA MAY SEE QPF AMOUNTS FROM 1-2". ANOTHER LATE SEASON  
GIFT THAT MAY ALLOW US TO AVOID A DANGEROUS FWX SEASON BEFORE THE  
MONSOON ARRIVES IN LATE JUNE.  
 
 
   
AVIATION...MONDAY 05/00Z THROUGH TUESDAY 06/00Z  
SCT -TSRA WILL  
CONTINUE THROUGH 02Z, WITH THUNDER BECOMING MOSTLY ISOLATED  
THEREAFTER. SCT -SHRA WILL CONTINUE FROM 02-10Z, THEN A STEADY  
REGION OF RA AND HIGH ELEVATION SN WILL FORM PRIMARILY TO THE WEST  
OF NAVAJO COUNTY. SCT -SHRA WILL CONTINUE ELSEWHERE. MVFR  
CONDITIONS ARE EXPECTED, AND REGIONS OF IFR-LIFR CIGS COULD  
PERSIST THROUGH 00Z TUESDAY. WINDS ARE LIGHT AND VRB OVERNIGHT AND  
SW 10-15 KTS TOMORROW. GUSTY AND RAPIDLY CHANGING WIND ARE  
POSSIBLE NEAR SHOWERS.  
 
OUTLOOK...TUESDAY 06/00Z THROUGH THURSDAY 08/00Z...CONTINUED  
AREAS OF -SHRA/-SHSN AND SOME ISOLATED -TSRA THROUGHOUT THE  
PERIOD, WITH THE HIGHEST COVERAGE THROUGH 12Z WED. WIDESPREAD MVFR  
WITH AREAS IFR/LIFR THROUGH TUESDAY MORNING, THEN AREAS MVFR  
THEREAFTER. WINDS ARE W-NW 5-10 KTS ON TUESDAY AND WEDNESDAY.  
GUSTY AND RAPIDLY CHANGING WIND ARE POSSIBLE NEAR SHOWERS.  
 
 
   
FIRE WEATHER...THIS AFTERNOON THROUGH TUESDAY  
COOLER WITH SHOWERS  
AND THUNDERSTORMS AT TIMES. ACCUMULATING SNOW POSSIBLE ABOVE 6500-  
7000 FEET LATE TONIGHT AND MONDAY. SOUTH-SOUTHWEST WINDS 15-20 MPH  
WITH GUSTS TO 25-35 MPH THROUGH EARLY THIS EVENING. WEST-SOUTHWEST  
WINDS DECREASE TO 10-15 MPH MONDAY AND TUESDAY.  
 
WEDNESDAY THROUGH FRIDAY...COOL AND SHOWERY WEATHER CONTINUES  
WEDNESDAY WITH A FEW THUNDERSTORMS ALSO POSSIBLE. BECOMING DRY AND  
MUCH WARMER THURSDAY AND FRIDAY. WINDS WEST-NORTHWEST 5-15 MPH ON  
WEDNESDAY, LIGHT AND VARIABLE TO NORTHEAST THURSDAY AND FRIDAY.  
 
 
   
FGZ WATCHES/WARNINGS/ADVISORIES  
NONE.  
 
 
 
 
 
PUBLIC...PETERSON  
AVIATION...LEWANDOWSKI  
FIRE WEATHER...JJ  
 
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT  
WEATHER.GOV/FLAGSTAFF  
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