915  
FXUS65 KPSR 152053  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
153 PM MST SUN JUN 15 2025  
   
KEY MESSAGES
 
 
- HOT AND DRY WEATHER IS FORECAST THROUGHOUT THE ENTIRE UPCOMING  
WEEK WITH THE HOTTEST DAYS EXPECTED TO BE TODAY AND THURSDAY.  
 
- AN EXTREME HEAT WARNING IS CURRENTLY IN EFFECT THROUGH MONDAY  
EVENING FOR HIGH TEMPERATURES RANGING FROM 109 TO 115 DEGREES  
ACROSS THE LOWER DESERTS.  
 
- WIDESPREAD MODERATE HEATRISK WILL BE SEEN FROM TUESDAY THROUGH  
FRIDAY WITH HIGH TEMPERATURES RANGING FROM 107 TO 115 DEGREES  
ACROSS THE LOWER DESERTS.  
 

 
   
DISCUSSION
 
 
CONTINUED HOT AND DRY WEATHER CONDITIONS WILL BE THE MAIN WEATHER  
STORY FOR THE UPCOMING WORKWEEK AS A STRONG SUBTROPICAL RIDGE OF  
HIGH PRESSURE PERSISTS OVER THE REGION. LATEST AFTERNOON OBJECTIVE  
ANALYSIS SHOWS THE SUBTROPICAL RIDGE CENTERED OVER SOUTHWEST NEW  
MEXICO WITH 500 MB HEIGHTS ACROSS OUR AREA AROUND 593-595 DM (90-  
99TH CLIMATOLOGICAL PERCENTILE). THE HOTTEST TEMPERATURES SO FAR  
THIS YEAR ARE EXPECTED THIS AFTERNOON AS A RESULT, WITH HIGHS  
EXPECTED TO TOP OUT AROUND 111-115 DEGREES FOR MOST LOWER DESERT  
LOCALES. IN PHOENIX, TEMPERATURES WILL FLIRT WITH THE DAILY RECORD  
HIGH OF 115 DEGREES LAST SET IN 2021. GIVEN THESE TEMPERATURES,  
WIDESPREAD MAJOR HEATRISK WILL COVER MUCH OF THE LOWER DESERTS AND  
INTO THE SOUTHERN GILA COUNTY HIGH TERRAIN TODAY. FOR MONDAY,  
FORECAST AFTERNOON HIGHS ONLY DROP 1-3 DEGREES WITH CONTINUED  
AREAS OF MAJOR HEATRISK. AN EXTREME HEAT WARNING REMAINS IN EFFECT  
THROUGH MONDAY EVENING FOR MOST OF THE AREA.  
 
GOING INTO EARLY TUESDAY, A WEAK SHORTWAVE TROUGH IS SET TO MOVE  
THROUGH NORTHERN PORTIONS OF THE STATE AND WILL BRIEFLY FLATTEN  
OUT THE RIDGE AND LOWER OUR HEIGHTS DURING THE FIRST PART OF THE  
WEEK. ENSEMBLE GUIDANCE SHOW 500 MB HEIGHTS LOWERING TO AROUND 590  
DM BEFORE RISING AGAIN GOING INTO WEDNESDAY FOLLOWING THE PASSAGE  
OF THE TROUGH. THE PASSAGE OF THIS WEAK SHORTWAVE WILL RESULT IN  
DAYTIME HIGHS TUESDAY DROPPING 2-4 DEGREES COMPARED TO MONDAY.  
THIS "COOL DOWN" WON'T LAST FOR LONG AS THE SUBTROPICAL RIDGE  
BUILDS BACK OVER THE REGION WITH 500 MB HEIGHTS RISING TO AROUND  
592-594 DM BY THURSDAY. TEMPERATURES WILL ONCE AGAIN HEAT UP FOR  
THE MIDDLE PART OF THE WEEK, WITH THURSDAY EXPECTED TO BE THE  
HOTTEST DAY AS HIGHS PUSH UPWARDS OF 110-115 DEGREES ACROSS THE  
LOWER DESERTS. DESPITE TECHNICALLY HAVING A BRIEF BREAK IN THE  
EXTREME HEAT CONDITIONS ON TUESDAY AND PERHAPS WEDNESDAY, WE WILL  
LIKELY NEED TO EITHER EXTEND THE CURRENT EXTREME HEAT WARNING  
THROUGH THE WORKWEEK OR REISSUE AGAIN FOR A DAY OR TWO LATER THIS  
WEEK. WIDESPREAD MODERATE HEATRISK IS EXPECTED THROUGH MUCH OF THE  
WORKWEEK, HOWEVER, TEMPERATURES ARE EXPECTED TO FLIRT WITH MAJOR  
HEATRISK THRESHOLDS THROUGHOUT THE WEEK.  
   
PREVIOUS DISCUSSION
 
 
BY AROUND FRIDAY INTO NEXT WEEKEND, ENSEMBLES FAVOR A LARGER  
PACIFIC TROUGH DIVING SOUTHEASTWARD ACROSS THE PACIFIC NORTHWEST,  
LIKELY INTO AT LEAST THE GREAT BASIN AREA. FOR NOW, GUIDANCE  
SUGGESTS THIS WILL EVENTUALLY DISPLACE THE SUB-TROPICAL RIDGE WELL  
TO OUR EAST LATE NEXT WEEKEND, LIKELY GIVING US A REPRIEVE FROM  
THE ABOVE NORMAL TEMPERATURES. NBM FORECAST TEMPERATURES FOR NEXT  
WEEKEND SHOW HIGHS DROPPING MORE INTO A 102-108 DEGREE RANGE DUE  
TO THE PASSING TROUGH, AS WELL AS PARTIALLY DUE A SLIGHT UPTICK IN  
LOW LEVEL MOISTURE. MODELS HAVE BEEN FAIRLY CONSISTENT IN SHOWING  
A GRADUAL MOISTURE INCREASE (AT LEAST INTO EASTERN ARIZONA)  
DURING THE LAST WEEK OF JUNE, BUT IT BARELY LOOKS TO BE ENOUGH TO  
BRING HIGHER TERRAIN SPOTTY CONVECTION.  
 

 
   
AVIATION
 
UPDATED AT 1725Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:  
NO AVIATION WEATHER CONCERNS WILL EXIST THROUGH THE TAF PERIOD  
UNDER CLEAR SKIES. WINDS WILL FOLLOW TYPICAL DIURNAL PATTERNS,  
WITH SPEEDS REMAINING GENERALLY AOB 10 KTS THROUGH MONDAY MORNING  
AND PERIODS OF VARIABILITY DURING TRANSITION PERIODS. AN EARLIER  
THAN USUAL SWITCH TO WEST WINDS IS EXPECTED BY LATE MONDAY  
MORNING, WITH GUSTS TO 15-20 KTS BECOMING COMMON DURING THE  
AFTERNOON (AFTER THE CURRENT 24-HR FORECAST PERIOD.)  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION WEATHER CONCERNS WILL EXIST THROUGH MONDAY MORNING  
UNDER CLEAR SKIES. WINDS WILL GENERALLY FOLLOW FAMILIAR PATTERNS,  
FAVORING S/SE THIS AFTERNOON INTO THE EARLY EVENING BEFORE  
SHIFTING SW/W AT BOTH TERMINALS. SPEEDS SHOULD REMAIN MOSTLY AOB  
10 KTS EXCEPT AT KIPL THIS EVENING, WHERE A PERIOD OF WSW'RLY  
GUSTS TO AROUND 15-20 KTS LOOKS LIKELY (>60% CHANCE).  
 

 
   
FIRE WEATHER
 
 
STRONG HIGH PRESSURE WILL CONTINUE TO BRING HOT AND SEASONABLY  
DRY CONDITIONS BEFORE A WEAK AND DRY DISTURBANCE BRUSHES ACROSS  
NORTHERN PORTIONS OF THE REGION MONDAY NIGHT INTO TUESDAY.  
TEMPERATURES WILL REMAIN ABOVE NORMAL WITH HIGHS NEAR OR ABOVE 110  
DEGREES EACH DAY ACROSS THE LOWER DESERTS. WIND PATTERNS WILL  
CONTINUE TO FOLLOW DIURNAL TRENDS (UPSLOPE AND DOWNVALLEY) WITH  
AFTERNOON GUSTS UP TO AROUND 20-25 MPH THE NEXT COUPLE OF DAYS,  
PARTICULARLY ACROSS THE HIGHER TERRAIN EAST OF PHOENIX. HUMIDITIES  
WILL STAY LOW WITH MINRHS BETWEEN 5-10% AND OVERNIGHT MAXRHS ONLY  
BETWEEN 15-30%. AFTERNOON GUSTS COMBINED WITH THE DRY CONDITIONS  
MAY LEAD TO SOME ELEVATED FIRE WEATHER CONDITIONS, ESPECIALLY  
ACROSS THE HIGHER TERRAIN EAST OF PHOENIX. HIGH PRESSURE WILL  
REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE REST OF THE WEEK  
WITH TEMPERATURES REMAINING ABOVE NORMAL THROUGH AT LEAST FRIDAY  
AND AFTERNOON MINRHS LIKELY STAYING BETWEEN 5-10% EACH DAY.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...EXTREME HEAT WARNING UNTIL 8 PM MST MONDAY FOR AZZ530>544-  
546>556-559>562.  
 
CA...EXTREME HEAT WARNING UNTIL 8 PM PDT MONDAY FOR CAZ562>567-569-  
570.  
 

 
 

 
 
DISCUSSION...SMITH  
PREVIOUS DISCUSSION...KUHLMAN  
AVIATION...WHITTOCK  
FIRE WEATHER...SMITH/KUHLMAN  
 
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