850  
FXUS65 KPSR 311738  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1038 AM MST FRI JUL 31 2026  
   
UPDATE
 
UPDATED AVIATION DISCUSSION.  
 

 
   
KEY MESSAGES
 
 
- EXTREME HEAT WILL PERSIST OVER THE REGION THROUGH AT LEAST THE  
WEEKEND WITH RECORD TO NEAR RECORD TEMPERATURES AND HIGHS  
TOPPING 115 DEGREES OVER MUCH OF THE LOWER DESERTS.  
 
- IN RESPONSE TO THE VERY HOT CONDITIONS, EXTREME HEAT WARNINGS  
ARE IN EFFECT REGIONWIDE THROUGH MONDAY.  
 
- DRIER AIR OVER THE REGION WILL CONFINE ANY CHANCES FOR SHOWERS  
AND THUNDERSTORMS OVER FAR EASTERN ARIZONA HIGH TERRAIN AREAS  
THROUGH AT LEAST MONDAY.  
 

 
   
SHORT TERM /TODAY THROUGH SUNDAY/
 
 
A DANGEROUS HEAT DOME CONTINUES TO STRENGTHEN ACROSS THE  
SOUTHWESTERN U.S. WITH H5 HEIGHTS SLATED TO REACH CLIMATOLOGICAL  
RECORDS LATER TODAY AND LAST THROUGH SATURDAY. THE CENTER OF THE  
RIDGE WILL SETTLE DIRECTLY OVER ARIZONA TODAY AS H5 HEIGHTS CLIMB  
TO 598-600DM BY LATE AFTERNOON. THE BOUNDARY LAYER HAS ALSO DRIED  
OUT ENOUGH TO LIMIT CONVECTIVE CHANCES OVER THE NEXT 2-3 DAYS,  
ESPECIALLY WITH SUBSIDENCE INCREASING DUE TO THE STRENGTHENING  
RIDGE. ENOUGH RESIDUAL MOISTURE SHOULD STILL ALLOW FOR SOME  
ISOLATED SHOWERS AND WEAK THUNDERSTORMS DURING THE AFTERNOON HOURS  
FROM THE WHITE MOUNTAINS INTO PORTIONS OF THE MOGOLLON RIM.  
TEMPERATURES ARE FORECAST TO REACH NEAR OR EVEN POSSIBLY BREAK  
DAILY RECORDS TODAY THROUGH SUNDAY WITH THE SOUTH-CENTRAL ARIZONA  
LOWER DESERTS TOPPING OUT BETWEEN 113-117 DEGREES TO AS HIGH AS  
116-120 DEGREES ACROSS SOUTHEAST CALIFORNIA. OVERNIGHT LOWS WILL  
ALSO BECOME EVEN MORE UNCOMFORTABLE WITH MOST LOCATIONS ONLY  
DIPPING INTO THE UPPER 80S TO THE LOWER 90S FROM FRIDAY NIGHT  
THROUGH SUNDAY NIGHT. THE EXTREME HEAT WARNING REMAINS IN EFFECT  
THROUGH MONDAY EVENING.  
 

 
   
LONG TERM /MONDAY THROUGH THURSDAY/
 
 
THE RIDGE IS FORECAST TO WEAKEN SUNDAY INTO MONDAY WITH H5  
HEIGHTS DROPPING TO 594-596DM OR RIGHT AROUND THE 90TH PERCENTILE  
OF CLIMATOLOGY. DESPITE THE RIDGE WEAKENING, THE RESIDUAL HEAT  
DOME WILL TAKE SOME TIME TO COOL AS FORECAST HIGHS MONDAY ONLY  
DROP A COUPLE DEGREES FROM SUNDAY'S READINGS, KEEPING THE HEATRISK  
AT MAJOR TO EXTREME FOR MUCH OF THE AREA. AS THE RIDGE WEAKENS  
AND ALSO SHIFTS ITS ORIENTATION SOME, MOISTURE SHOULD BEGIN TO  
INCREASE AGAIN ACROSS SOUTHEAST ARIZONA ON SUNDAY AND THEN  
EVENTUALLY OVER ALL OF SOUTHERN AND CENTRAL ARIZONA MONDAY INTO  
TUESDAY. AS A RESULT, CONVECTIVE POTENTIAL WILL TICK UPWARDS EARLY  
NEXT WEEK, FIRST OVER THE ARIZONA HIGHER TERRAIN AND EVENTUALLY  
INTO THE LOWER DESERTS DURING THE MIDDLE PART OF NEXT WEEK. THE  
EXPECTED INCREASE IN CONVECTION IS LIKELY TO HELP TO COOL THINGS  
OFF TUESDAY INTO WEDNESDAY, DROPPING THE HEATRISK INTO A HIGH-END  
MODERATE TO LOW-END MAJOR. THERE IS STILL A GOOD AMOUNT OF  
UNCERTAINTY AS FAR AS THE STORM CHANCES DURING THE FIRST HALF OF  
NEXT WEEK, SO ANY DELAY IN THE MOISTURE MAY RESULT IN HAVING TO  
EXTEND THE EXTREME HEAT WARNING ANOTHER DAY OR SO FOR PORTIONS OF  
THE AREA.  
 

 
   
AVIATION
 
UPDATED AT 1738Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
 
NO MAJOR AVIATION WEATHER CONCERNS WILL EXIST THROUGH SATURDAY  
MORNING UNDER PERIODS OF MID/HIGH CLOUD DECKS. WINDS WILL  
PREDOMINANTLY FAVOR A WESTERLY COMPONENT THROUGH MUCH OF THE TAF  
PERIOD WITH A BRIEF PERIOD OF EASTERLY OR LIGHT AND VARIABLE  
WINDS ANTICIPATED EARLY SATURDAY MORNING. OCCASIONAL AFTERNOON  
GUSTS INTO THE TEENS ARE EXPECTED TODAY AND TOMORROW. A FEW HIGH-  
BASED SHOWERS OR VIRGA MAY INFRINGE ON THE EASTERN EDGES OF THE  
PHOENIX AREA EARLY SATURDAY MORNING, HOWEVER, CONFIDENCE IS TOO  
LOW TO INCLUDE IN ANY TAFS.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
NO MAJOR AVIATION WEATHER CONCERNS WILL EXIST THROUGH THE NEXT 24  
HOURS UNDER MOSTLY CLEAR SKIES. WINDS AT KIPL WILL FAVOR AN E/SE  
COMPONENT THROUGHOUT MUCH OF THE PERIOD, WHILE WINDS AT KBLH WILL  
VARY BETWEEN THE S AND SW. SPEEDS WILL MOSTLY REMAIN AOB 10 KTS  
WITH OCCASIONAL AFTERNOON GUSTS INTO THE TEENS AT KBLH.  
 

 
   
FIRE WEATHER
 
 
STRONG HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH THE  
WEEKEND WHILE RELATIVELY DRY AIR CONFINES ANY RAIN CHANCES TO  
OVER FAR EASTERN ARIZONA. EXPECT DAILY MINRHS MOSTLY BETWEEN  
10-15%, WHILE FALLING OVERNIGHT RHS OFFER ONLY LITTLE TO MODEST  
RELIEF. RECORD TO NEAR RECORD TEMPERATURES ARE ALSO FORECAST TODAY  
AND THROUGH THE WEEKEND. WINDS WILL MOSTLY FOLLOW DIURNAL  
PATTERNS, BUT WEST SOUTHWESTERLY WINDS WILL BE DOMINANT MUCH OF  
THE TIME WITH AFTERNOON GUSTS OF 15-20 MPH AT TIMES.  
 

 
   
CLIMATE
 
 
RECORD HIGH TEMPERATURES:  
 
DATE PHOENIX YUMA EL CENTRO  
---- ------- ---- ---------  
JUL 31 116 IN 2020 119 IN 1957 119 IN 2020  
AUG 1 116 IN 1972 117 IN 1993 118 IN 1993  
AUG 2 114 IN 2025 117 IN 1918 117 IN 1969  
AUG 3 116 IN 2024 116 IN 1998 117 IN 2021  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...EXTREME HEAT WARNING UNTIL 8 PM MST MONDAY FOR AZZ530>563.  
 
CA...EXTREME HEAT WARNING UNTIL 8 PM PDT MONDAY FOR CAZ560>570.  
 

 
 

 
 
SHORT TERM...KUHLMAN  
LONG TERM...KUHLMAN  
AVIATION...SMITH/BENEDICT  
FIRE WEATHER...KUHLMAN  
CLIMATE...18  
 
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