062  
FXUS65 KPSR 020541  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1041 PM MST WED OCT 1 2025  
   
UPDATE
 
UPDATED AVIATION DISCUSSION.  
 

 
   
KEY MESSAGES
 
 
- HIGH PRESSURE WILL CONTINUE TO PROMOTE DRY AND QUIET CONDITIONS  
OVER THE NEXT FEW DAYS  
 
- DAY-TO-DAY TEMPERATURES WILL CONTINUE TO SLOWLY CLIMB, PEAKING  
THURSDAY WITH A FEW LOCATIONS REACHING INTO THE TRIPLE DIGITS.  
 
- LOW PRESSURE WILL BRUSH THE DESERT SOUTHWEST LATE THIS WEEK AND  
INTO THE WEEKEND BRINGING BREEZY TO LOCALLY WINDY CONDITIONS AND  
COOLING TEMPERATURES.  
 
 

 
   
SHORT TERM /TODAY THROUGH THURSDAY/
 
 
AFTERNOON ATMOSPHERIC ANALYSIS REVEALS MINIMAL CHANGE IN THE  
OVERALL PATTERN OVER THE WESTERN CONUS WITH HIGH PRESSURE BUILDING  
OVER THE DESERT SOUTHWEST AND BROAD TROUGHING OVER THE PACIFIC  
NORTHWEST AND NORTHERN ROCKIES. THESE TWO WEATHER REGIMES ARE  
CURRENTLY NUDGING AT EACH OTHER FOR CONTROL OVER CONDITIONS ACROSS  
OUR FORECAST AREA, BUT AT LEAST IN THE NEAR TERM, THE AREA OF  
HIGH PRESSURE WILL WIN OUT, STAVING OFF ANY ADVANCEMENT OF THE  
PACIFIC LOW AT LEAST UNTIL THE END OF THE WEEK. FOR US, THAT MEANS  
MORE DRY CONDITIONS AND A STEPWISE LIKE UPTREND IN TEMPERATURES  
OVER THE NEXT FEW DAYS. READINGS THIS AFTERNOON ACROSS THE LOWER  
DESERTS WILL BE SIMILAR TO YESTERDAY, WITH VALUES GENERALLY IN THE  
MIDDLE 90S. AS THE HIGH AMPLIFIES FURTHER HEADING INTO THURSDAY,  
TEMPERATURES WILL TICK UP A FEW DEGREES, WITH SOME LOCATIONS  
SEEING THE RETURN OF TRIPLE DIGITS. IT IS NOT OUT OF THE ORDINARY  
TO SEE THE CENTURY MARK ON THE THERMOMETER IN EARLY OCTOBER  
(THOUGH IF YOU LOOK AT LAST YEAR, ONE MIGHT THINK IT IS) AS THE  
AVERAGE LAST TRIPLE DIGIT DAY AT SKY HARBOR AT LEAST IS OCTOBER  
5TH.  
 

 
   
LONG TERM /FRIDAY THROUGH TUESDAY/
 
 
ENSEMBLE AND DETERMINISTIC MODELS REMAIN IN AGREEMENT THAT TROUGHING  
OVER THE PAC NW WILL DEEPENS OVER CALIFORNIA AND SLIDE INTO THE  
GREAT BASIN ON FRIDAY. AS THIS OCCURS, 500 MB HGHTS WILL BEGIN TO  
LOWER ACROSS THE WESTERN HALF OF THE FORECAST AREA, BUT 500 MB HGHTS  
WILL STILL HOVER AROUND 588-590 DAM OVER SOUTHCENTRAL AZ. NEGATIVE  
HGHT ANOMALIES WILL ARRIVE FIRST IN SOUTHEAST CA FRIDAY AFTERNOON  
WHERE HIGH TEMPERATURES WILL BE SLIGHTLY COOLER IN THE LOW TO MID  
90S. HOWEVER HIGHS WILL STILL BE ABOVE AVERAGE IN SOUTHCENTRAL AZ IN  
THE UPPER 90S TO 100 DEGREES. DUE TO THE TIGHTENING 700-500 MB HGHT  
GRADIENT, WE WILL SEE A NOTICEABLE UPTICK IN WINDS WITH BREEZY  
CONDITIONS MATERIALIZING ACROSS MUCH OF THE REGION FRIDAY AFTERNOON.  
THE STRONGEST WINDS (>30 MPH) WILL LIKELY RESIDE ACROSS SOUTHEAST  
CA AND THE HIGH COUNTRY OF NORTHERN AZ.  
 
THE TROUGH AXIS WILL PASS OVER N AZ ON SATURDAY MORNING WHICH WILL  
DRAG A PACIFIC COLD FRONT THROUGH THE FORECAST AREA. POST FRONTAL  
WINDS WILL CONTINUE TO GUST AROUND 20-30 MPH ACROSS SOUTHEAST CA AND  
THE LOWER COLORADO RIVER VALLEY EARLY SATURDAY. 500 MB HGHTS WILL  
LOWER BACK TO SEASONAL RANGES THIS WEEKEND AND INTO EARLY NEXT WEEK,  
WHICH WILL FOSTER TEMPERATURES COOLING BACK TO NEAR NORMAL SATURDAY  
THROUGH EARLY NEXT WEEK. MUCH DRIER AIR WILL ALSO BE USHERED INTO  
THE REGION IN THE WAKE OF THIS WEATHER SYSTEM WHICH WILL ALLOW  
MORNING LOWS TO FEEL MUCH MORE FALL-LIKE IN THE LOW TO MID 60S  
ACROSS THE LOWER DESERTS.  
 

 
   
AVIATION
 
UPDATED AT 0540Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION WEATHER CONCERNS ARE ANTICIPATED THROUGH THURSDAY  
EVENING. WINDS WILL OVERALL CONTINUE TO FOLLOW TYPICAL DIURNAL  
TENDENCIES WITH SPEEDS AOB 7 KTS THROUGH MOST OF THE TAF PERIOD.  
EXPECT A LIGHT SOUTHERLY COMPONENT TO DEVELOP BY MIDDAY THURSDAY  
BEFORE VEERING TOWARDS THE W-SW THURSDAY AFTERNOON. EXTENDED  
PERIODS OF LIGHT AND VARIABLE TO CALM WINDS ARE ALSO EXPECTED  
THROUGHOUT THE PERIOD. SKIES WILL CONTINUE TO BE CLEAR.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION WEATHER CONCERNS ARE EXPECTED THROUGH THE NEXT 24  
HOURS. WINDS AT KIPL WILL FAVOR THE W THROUGH MUCH OF THE PERIOD,  
WHILE WINDS AT KBLH MOSTLY FAVOR THE S. EXPECT WINDS TO REMAIN  
LIGHT, MOSTLY AOB 10 KTS, THROUGH MUCH OF THE TAF PERIOD WITH  
PERIODS OF LIGHT AND VARIABLE TO CALM CONDITIONS. SKIES WILL  
CONTINUE TO BE CLEAR.  
 

 
   
FIRE WEATHER
 
 
TEMPERATURES WILL CLIMB ABOVE NORMAL THROUGH THE END OF THIS WEEK AS  
A RIDGE OF HIGH PRESSURE STRENGTHENS OVER THE FORECAST AREA. EXPECT  
DRY CONDITIONS TO PERSIST WITH MINRHS BOTTOMING OUT EACH AFTERNOON  
AROUND 25-35%. OVERNIGHT MOISTURE RECOVERY WILL GENERALLY REMAIN  
IN THE FAIR CATEGORY AROUND 40-60%. WINDS WILL FOLLOW LIGHT AND  
DIURNAL TENDENCIES THROUGH THURSDAY, HOWEVER A WEATHER SYSTEM  
PASSING NORTH OF THE REGION WILL RESULT IN AN UPTICK IN BREEZY  
CONDITIONS ACROSS THE REGION ON FRIDAY. EXPECT GUSTS TO INCREASE  
TO AROUND 20-25 MPH REGION-WIDE WITH LOCALLY HIGHER GUSTS UPWARDS  
OF 30 MPH BOTH FRIDAY AND SATURDAY. THE PASSAGE OF THIS WEATHER  
SYSTEM WILL ALSO RESULT IN THE ARRIVAL OF COOLER TEMPERATURES AND  
MUCH DRIER AIR THROUGH THIS WEEKEND.  
 

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

 
 

 
 
SHORT TERM...RW  
LONG TERM...SALERNO  
AVIATION...SMITH/BENEDICT  
FIRE WEATHER...SALERNO  
 
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