876  
FXUS65 KPSR 022323  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
423 PM MST SUN AUG 2 2026  
   
UPDATE...UPDATED 00Z AVIATION DISCUSSION
 
 

 
   
KEY MESSAGES
 
 
- EXTREME HEAT WILL PERSIST THROUGH THE START OF THE WEEK WITH  
HIGH TEMPERATURES TOPPING OUT IN THE 110 TO 118 DEGREE RANGE  
OVER MUCH OF THE LOWER DESERTS, HOVERING RIGHT AROUND RECORD  
LEVELS.  
 
- EXTREME HEAT WARNINGS ARE IN EFFECT REGIONWIDE THROUGH TUESDAY.  
 
- HIGH PRESSURE AND DRIER AIR OVER THE REGION WILL CONFINE  
SHOWERS AND THUNDERSTORMS PRIMARILY TO FAR EASTERN AND  
SOUTHEASTERN ARIZONA AREAS THROUGH AT LEAST MONDAY.  
 
- SHOWER AND THUNDERSTORM CHANCES INCREASE ACROSS SOUTH-CENTRAL  
ARIZONA BY THE SECOND HALF OF THE WEEK.  
 

 
   
SHORT TERM /TODAY THROUGH TUESDAY/
 
 
A STRONG RIDGE OF HIGH PRESSURE REMAINS SITUATED OVER THE DESERT  
SOUTHWEST AND CONTINUES TO PROMOTE WELL ABOVE NORMAL TEMPERATURES  
ACROSS THE REGION THIS AFTERNOON. THIS MORNING'S 12Z PHX AND 18Z FGZ  
SOUNDINGS SAMPLED A 500 MB HEIGHT OF 598 DM; THOUGH THE RIDGE  
REMAINS QUITE STRONG, A WEAKENING TREND IS UNDERWAY AS A TROUGH  
PASSES THROUGH THE PACIFIC NW/BC/ALBERTA. BY TOMORROW, 500 MB  
HEIGHTS WILL LOWER TO AROUND 594-595 DM, WHICH IS STILL ABOVE THE  
90TH CLIMATOLOGICAL PERCENTILE. AFTERNOON TEMPERATURES MONDAY ARE  
FORECAST TO SEE A ~2-4 DEGREE DROP FROM TODAY WITH HIGHS TOPPING OUT  
BETWEEN 111-116 DEGREES FOR MOST LOWER DESERT LOCATIONS. MORNING  
LOWS WILL ALSO REMAIN QUITE WARM, OFFERING LIMITED RELIEF FROM THE  
HEAT AS TEMPERATURES ONLY FALL INTO THE MID/UPPER 80S TO LOW 90S.  
AS A RESULT, MAJOR TO EXTREME HEATRISK WILL BE IN PLACE ACROSS  
MANY LOWER DESERT LOCALES MONDAY, THOUGH SEEING A NOTABLE DECREASE  
FROM THE WIDESPREAD COVERAGE IN PLACE TODAY. AFTERNOON  
TEMPERATURES TUESDAY WILL SEE ANOTHER ~2-4 DEGREE DROP, HOWEVER,  
GUIDANCE CONTINUE TO FAVOR INCREASING BOUNDARY LAYER MOISTURE  
HEADING INTO THE MIDDLE PART OF THE WEEK, WHICH WILL MAKE FOR MORE  
HUMID CONDITIONS. THIS ADDED MOISTURE WILL PUSH HEAT INDICES  
UPWARDS OF 112-118 DEGREES, PARTICULARLY ACROSS SOUTHEAST  
CALIFORNIA AND SOUTHWEST ARIZONA. EXTREME HEAT WARNINGS REMAIN IN  
EFFECT FOR MUCH OF THE AREA THROUGH TUESDAY EVENING.  
 
MONSOONAL ACTIVITY IS EXPECTED TO REMAIN LIMITED ACROSS OUR AREA  
THROUGH THE START OF THE NEW WORKWEEK WITH LIMITED MOISTURE AND  
STRONG HIGH PRESSURE PROMOTING SUBSIDENCE. FOR TODAY, STORMS WILL  
AGAIN FAVOR FAR EASTERN AND SOUTHEASTERN ARIZONA. STRONG OUTFLOWS  
EMANATING FROM THESE STORMS ARE EXPECTED TO PUSH INTO SOUTHERN GILA  
COUNTY AND MAY BE ENOUGH TO POP OFF A FEW ISOLATED SHOWERS AND  
STORMS. ANY NEW STORM DEVELOPMENT THAT WERE TO OCCUR WOULD BE  
CAPABLE OF PRODUCING STRONG, ERRATIC WINDS. STORM ACTIVITY WILL  
CONTINUE TO PRIMARILY FAVOR EASTERN AND SOUTHEASTERN PORTIONS OF THE  
STATE AS NORTHEASTERLY STEERING FLOW KEEPS MUCH OF THIS ACTIVITY  
OUTSIDE OF OUR CWA. MONDAY LOOKS TO BE A PARTICULARLY ACTIVE DAY FOR  
SOUTHEAST AZ, WITH FAVORABLE SHEAR AND INSTABILITY FOR SOME  
ORGANIZED STORM CLUSTERS. GIVEN HIGH DCAPE MAGNITUDES (>1500 J/KG),  
THE STORMS IN SOUTHEAST AZ MONDAY WILL BE CAPABLE OF SENDING  
OUTFLOWS, POTENTIALLY STRONG AND WITH DUST, WESTWARD AND NORTHWARD  
THROUGH PINAL COUNTY. THESE OUTFLOWS AND A GULF SURGE MONDAY NIGHT  
WILL BE THE DRIVER OF THE INCREASE IN MOISTURE HEADING INTO TUESDAY.  
WHILE THIS SOUNDS PROMISING FOR STORM CHANCES ACROSS THE LOWER  
DESERTS HEADING INTO TUESDAY, WITH MUCH BETTER INSTABILITY,  
SUBSIDENCE, PERSISTENT VERY WARM TEMPERATURES ALOFT, AND FAIRLY HIGH  
INHIBITION WILL CONTINUE TO COUNTER/HINDER CONVECTIVE POTENTIAL.  
THUS, NBM POPS REMAIN LOW FOR OUR AREA, WITH THE BEST CHANCES  
RESIDING ACROSS FAR SOUTHERN AND EASTERN GILA COUNTY WHERE CHANCES  
CLIMB TO 20-30% BY TUESDAY.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SATURDAY/
 
 
AFTER WEAKENING SLIGHTLY TO START THE WEAK, GLOBAL ENSEMBLES  
SUPPORT THE SUBTROPICAL HIGH RESTRENGTHENING DURING THE SECOND  
HALF OF THE WEEK, BACK UP TO A 600DAM HIGH, BUT ALSO DRIFTING A  
LITTLE FURTHER NORTH TOWARD/INTO UT. H5 HEIGHTS OVER THE LOCAL  
AREA ARE FORECAST TO CLIMB BACK UP TO A PEAK OF AROUND 596-597DAM  
BY FRIDAY. COOLEST TEMPERATURES OVER THE NEXT WEEK ARE FORECAST  
FOR WEDNESDAY, BUT TEMPERATURES WILL STILL BE ABOVE NORMAL WITH  
LOWER DESERT HIGHS IN THE 106-112 DEGREE RANGE. DESPITE THE  
RESTRENGTHENING OF THE HIGH, HIGH TEMPERATURES ARE NOT FORECAST TO  
SEE A SIGNIFICANT INCREASE AGAIN, ROUGHLY 1 DEGREE EACH DAY  
THROUGH SATURDAY, LIKELY DUE TO THE THE INCREASED MOISTURE.  
HOWEVER, THE FORECAST CALLS FOR JUST ENOUGH WARMING TO ONCE AGAIN  
INCREASE THE COVERAGE OF MAJOR HEATRISK. MORNING LOW TEMPERATURES  
WILL LIKELY REMAIN QUITE WARM - BARRING ANY COOLING FROM STORMS -  
MOSTLY IN THE 80S TO RIGHT AROUND 90 DEGREES.  
 
WITH THE SMALL MOVEMENTS OF THE SUBTROPICAL HIGH MIDWEEK AND SHIFT  
NORTH LATE WEEK, THERE WILL BE A BETTER FETCH OF EASTERLY WINDS  
ACROSS SOUTHERN NEW MEXICO, SOUTHERN ARIZONA, AND NORTHERN MEXICO.  
ABOVE NORMAL MOISTURE IS ALSO SHOWN TO STICK AROUND THROUGH THE  
END OF THE WEEK AND NEXT WEEKEND, WITH 60S DEW POINTS. THIS  
PATTERN WILL AT LEAST SUPPORT DAILY ROBUST THUNDERSTORMS  
DEVELOPING OVER THE AZ HIGH TERRAIN, BUT THERE IS STILL  
UNCERTAINTY WHETHER STORMS CAN FIRE OFF OR SURVIVE INTO LOWER  
DESERT AREAS LIKE PHOENIX AND POINTS FURTHER WEST. STILL, THIS  
LOOKS LIKE THE BEST CHANCE OF THE SUMMER SO FAT FOR THUNDERSTORMS  
IN PORTIONS OF SOUTHWEST AZ AND SOUTHEAST CA, WHO HAVE BEEN  
LACKING FOR RAIN SO FAR THIS SUMMER. LATEST NBM/WPC FORECAST  
CONTINUES TO SHOW 10-30% POPS ACROSS MUCH OF SOUTH-CENTRAL  
ARIZONA BY THURSDAY AND CONTINUING THROUGH THE END OF THE WEEK. A  
PERIOD OF STRONGER MID-LEVEL EASTERLIES AND PERHAPS AND EASTERLY  
WAVE/IT WILL CERTAINLY IMPROVE THE ODDS OF STORM CHANCES ACROSS  
THE AREA STRONG TO SEVERE WIND GUSTS WILL BE POSSIBLE WITH MOST  
STORMS AND AN INCREASE IN MIXING RATIOS UP TO 11-12 G/KG LATE WEEK  
WILL SUPPORT VERY HEAVY RAINFALL.  
 

 
   
AVIATION
 
UPDATED AT 2320Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO MAJOR AVIATION WEATHER CONCERNS UNDER FEW TO OCCASIONALLY SCT  
MID TO HIGH-LEVEL CLOUD DECKS CAN BE EXPECTED THROUGH MONDAY  
AFTERNOON. THE OVERALL WIND PATTERN WILL FOLLOW THE TYPICAL  
DIURNAL TENDENCIES WITH SOME OCCASIONAL GUSTS OF AROUND 20 KTS  
THROUGH EARLY THIS EVENING AND ONCE AGAIN FOR MONDAY AFTERNOON.  
 
MONDAY EVENING OUTLOOK: A COMPLEX OF STRONG THUNDERSTORMS IS  
LIKELY TO DEVELOP ACROSS SOUTHEAST AZ MONDAY AFTERNOON/EVENING,  
SENDING A ROBUST OUTFLOW BOUNDARY NORTHWARD INTO SOUTH-CENTRAL AZ  
MONDAY EVENING, LIKELY AFTER 03-04Z. STRONG GUSTY WINDS OUT OF THE  
SOUTH WITH POTENTIAL PEAK GUSTS IN EXCESS OF 25-30 KTS AND LOFTED  
DUST POTENTIALLY REDUCING VISIBILITIES TO MVFR CONDITIONS WILL BE  
THE PRIMARLY HAZARDS. THERE IS A LOW CHANCE (10-20%) FOR ISOLATED  
THUNDERSTORM DEVELOPMENT ALONG THE OUTFLOW BOUNDARY ACROSS  
PORTIONS OF THE PHOENIX METRO MONDAY EVENING, HOWEVER, CONFIDENCE  
OF OCCURRENCE IS TOO LOW AT THIS TIME FOR INCLUSION IN THE TAFS.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
GUSTY SOUTHERLY WINDS, PRIMARILY AT KBLH MONDAY AFTERNOON, WILL BE  
THE MAIN AVIATION WEATHER ISSUE THROUGHOUT THE TAF PERIOD UNDER  
MOSTLY CLEAR SKIES. AT KIPL, WINDS WILL GENERALLY BE OUT OF THE  
SOUTHEAST WITH A TEMPORARY SHIFT OUT OF THE SOUTHWEST THIS  
EVENING. AT KBLH, WINDS WILL GENERALLY FLUCTUATE OUT OF THE SOUTH  
TO SOUTH-SOUTHWEST. OVERALL WIND SPEEDS WILL FLUCTUATE BETWEEN  
8-12 KTS, WITH GUSTS NEAR 20 KTS CONTINUING AT KBLH THROUGH EARLY  
THIS EVENING. ANOTHER ROUND OF ELEVATED GUSTS UPWARDS OF 25 KTS,  
OCCASIONALLY HIGHER, IS LIKELY ONCE MONDAY AFTERNOON AT KBLH.  
 

 
   
FIRE WEATHER
 
 
STRONG HIGH PRESSURE AND VERY HOT TEMPERATURES, WITH DRY  
CONDITIONS, WILL PERSIST INTO THE START OF THE NEW WORKWEEK.  
AFTERNOON HIGH TEMPERATURES WILL RANGE BETWEEN 110-115 DEGREES FOR  
MANY LOWER ELEVATION LOCATIONS OVER THE NEXT COUPLE OF DAYS. MIN  
RHS WILL GRADUALLY IMPROVE WITH VALUES RANGING BETWEEN 15-20%  
MONDAY BEFORE CLIMBING TO AROUND 20-25% TUESDAY. OVERNIGHT MAX RHS  
WILL ALSO IMPROVE, RISING FROM 35-50% OVERNIGHT TONIGHT TO 50-70%  
TUESDAY MORNING. THE INCREASING MOISTURE WILL RESULT IN AN  
INCREASE IN SHOWER AND STORM CHANCES. INITIALLY, STORM CHANCES  
THIS WEEKEND THROUGH THE START OF THE WEEK WILL FOCUS IN FAR  
EASTERN AND SOUTHEASTERN AZ, WITH POTENTIAL FOR STORM OUTFLOW  
WINDS TO PROGRESS INTO SOUTH-CENTRAL AZ. SLIGHT CHANCES FOR STORMS  
(15-30%) THEN SPREAD TO SOUTH-CENTRAL AZ BY THE MIDDLE AND SECOND  
HALF OF THE WEEK. OUTSIDE OF STORM OUTFLOWS, WINDS WILL MOSTLY  
FOLLOW DIURNAL PATTERNS, BUT WEST SOUTHWESTERLY WINDS WILL BE  
DOMINANT MUCH OF THE TIME WITH AFTERNOON GUSTS OF 15-25 MPH AT  
TIMES.  
 

 
   
CLIMATE
 
 
RECORD HIGH TEMPERATURES:  
 
DATE PHOENIX YUMA EL CENTRO  
---- ------- ---- ---------  
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 TUESDAY FOR AZZ530>544-546-  
548>551-553>555-559.  
 
EXTREME HEAT WARNING UNTIL 8 PM MST MONDAY FOR AZZ545-547-552-  
556>558-560>563.  
 
CA...EXTREME HEAT WARNING UNTIL 8 PM PDT TUESDAY FOR CAZ562-563-  
565>567-569-570.  
 
EXTREME HEAT WARNING UNTIL 8 PM PDT MONDAY FOR CAZ560-561-564-  
568.  
 

 
 

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