640  
FXUS65 KPSR 051706  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1005 AM MST THU JUN 5 2025  
   
UPDATE
 
 
UPDATED AVIATION  
 

 
   
DISCUSSION
 
 
KEY MESSAGES:  
 
- HOT AND DRY CONDITIONS ARE EXPECTED INTO NEXT WEEK WITH LOWER  
DESERT TEMPERATURES PEAKING NEAR 110 DEGREES ON SUNDAY AND MONDAY  
 
- AREAS OF MODERATE HEATRISK DEVELOP BY SATURDAY, LIKELY PERSISTING  
THROUGH THE MIDDLE PART OF NEXT WEEK  
 
DRIER AIR CONTINUES TO SPREAD INTO ARIZONA AND FAR SOUTHERN  
CALIFORNIA, DESPITE WEAK TROUGHING CENTERED OVER CENTRAL CALIFORNIA  
INTO THE GREAT BASIN. MOISTURE LEVELS HAVE DROPPED CONSIDERABLY  
ACROSS SOUTH-CENTRAL ARIZONA WITH PWATS NOW BELOW 1" AND SURFACE DEW  
POINTS AROUND 50 DEGREES. THE WESTERN DESERTS ARE STILL HOLDING ONTO  
SOME MOISTURE WITH PWATS BETWEEN 1-1.2" AND A BIT HIGHER DEW POINTS,  
BUT WITH THE LACK OF ANY GOOD FORCING TODAY THE AREA SHOULD STAY  
MOSTLY QUIET. LOCATIONS INTO SAN BERNARDINO CO. MAY SEE SOME  
ISOLATED SHOWERS OR THUNDERSTORMS THIS AFTERNOON, BUT HI-RES CAMS  
SHOW NO ACTIVITY INTO RIVERSIDE OR IMPERIAL COUNTIES.  
 
TODAY WILL ALSO MARK THE START OF THE SUB-TROPICAL RIDGE NUDGING  
INTO OUR REGION, WHICH IS CURRENTLY CENTERED OVER NORTHERN MEXICO  
AND SOUTHERN TEXAS. THIS RIDGE WILL HOWEVER NOT FULLY MAKE ITS WAY  
INTO OUR REGION AS THE LARGE SCALE TROUGHING TO OUR NORTH AND  
NORTHWEST SOMEWHAT KEEPS IT AT BAY. AS THE RIDGE PARTIALLY MOVES  
INTO OUR REGION OVER THE NEXT FEW DAYS, H5 HEIGHTS ARE SEEN RISING  
FROM AROUND 582DM TODAY TO AROUND 588DM BY SUNDAY. THIS WILL  
GRADUALLY PUSH TEMPERATURES UPWARD OVER THE NEXT SEVERAL DAYS WITH  
HIGHS AROUND NORMAL TODAY AND FRIDAY BEFORE PEAKING SUNDAY AND  
MONDAY BETWEEN 105-109 DEGREES ACROSS THE SOUTH-CENTRAL ARIZONA  
LOWER DESERTS AND 106-111 DEGREES ACROSS THE WESTERN DESERTS. THE  
PEAK TEMPERATURES SHOULD END UP AROUND 4-8 DEGREES ABOVE NORMAL, BUT  
STILL AT LEAST 5 DEGREES SHY OF DAILY RECORDS.  
 
THE HOT TEMPERATURES WILL PUSH MOST LOCATIONS INTO THE MODERATE  
HEATRISK CATEGORY STARTING SATURDAY. THIS WEATHER PATTERN OF THE SUB-  
TROPICAL RIDGE JUST TO OUR SOUTH AND A QUAI-ZONAL FLOW REGIME ACROSS  
THE NORTHERN TIER STATES SHOULD PERSIST THROUGH AT LEAST THE MIDDLE  
PART OF NEXT WEEK. ENSEMBLE GUIDANCE DOES SHOW OUR H5 HEIGHTS  
LOWERING A BIT INTO THE MIDDLE PART OF THE WEEK BEFORE A LARGER  
TROUGH EVENTUALLY TAKE SHAPE OFF THE NORTHWEST U.S. LATE NEXT WEEK.  
THIS SHOULD KNOCK A FEW DEGREES OFF OUR TEMPERATURES DURING THE  
MIDDLE PART OF NEXT WEEK AND POSSIBLY FEW MORE BY NEXT WEEKEND AS  
TEMPERATURES ARE LIKELY TO RETREAT BACK TO NEAR NORMAL. DRY  
CONDITIONS AND NEAR CONSISTENTLY CLEAR SKIES ARE EXPECTED FOR ALL OF  
NEXT WEEK UNDER THIS PATTERN.  
 

 
   
AVIATION
 
UPDATED AT 1705Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:  
NO MAJOR WEATHER ISSUES SHOULD EXIST THROUGH FRIDAY AFTERNOON UNDER  
A FEW MIDLEVEL CLOUD DECKS THROUGH THIS AFTERNOON. THE TYPICAL  
AFTERNOON WIND SHIFT MAY INCORPORATE SEVERAL HOURS OF VARIABLE  
DIRECTIONS WITH SPEEDS UNDER 8KT BEFORE SETTLING ON W/SW MID  
AFTERNOON THROUGH OVERNIGHT. CONFIDENCE IS MODERATE THAT THE  
OVERNIGHT SHIFT TO EASTERLY WILL BE LATER THIS USUAL, AND REVISION  
BACK TO WEST SLIGHTLY EARLIER FRIDAY.  
 
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO SIGNIFICANT WEATHER CONCERNS WILL EXIST THROUGH FRIDAY AFTERNOON  
UNDER CLEAR SKIES. S/SE WIND DIRECTIONS WILL BE FAVORED THROUGH THE  
PERIOD WITH SOME VARIABILITY AND BRIEF SW DIRECTIONAL SHIFTS  
POSSIBLE. CONFIDENCE IS GOOD THAT SPEEDS WILL PRIMARILY REMAIN BELOW  
10KT, HOWEVER COULD INCREASE CLOSER TO 15KT AT TIMES.  
 

 
   
FIRE WEATHER
 
 
DRYING CONDITIONS AND HOTTER TEMPERATURES ARE EXPECTED INTO THE  
WEEKEND. AFTERNOON MINRHS WILL DECREASE FROM 15-20% TODAY TO 7-12%  
BY SATURDAY AS LOWER DESERT HIGH TEMPERATURES INCREASE INTO THE  
LOWER TRIPLE DIGITS, WHICH IS NEAR NORMAL RANGE FOR THIS TIME OF  
YEAR. OVERNIGHT RHS WILL ALSO DECREASE FROM 30-45% TONIGHT TO 25-35%  
FRIDAY NIGHT. WINDS SHOULD FOLLOW FAIRLY TYPICAL DIURNAL TENDENCIES  
WITH PERIODIC AFTERNOON UPSLOPE GUSTINESS. THE DRY WEATHER PATTERN  
IS EXPECTED TO CONTINUE INTO EARLY NEXT WEEK WITH TEMPERATURES  
RUNNING 5-10 DEGREES ABOVE NORMAL AND DAILY MINRHS MOSTLY IN A 5-10%  
RANGE.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...NONE.  
CA...NONE.  
 

 
 

 
 
DISCUSSION...KUHLMAN  
AVIATION...18  
FIRE WEATHER...KUHLMAN  
 
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