232  
FXUS65 KPSR 292315  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
415 PM MST TUE SEP 29 2026  
   
UPDATE
 
 
UPDATED AVIATION  
 

 
   
KEY MESSAGES
 
 
- A FLOOD WATCH REMAIN IN EFFECT FOR PARTS OF THE REGION THROUGH  
THIS EVENING, HOWEVER MOST OF THE HEAVIEST RAIN HAS EXITED THE  
REGION.  
 
- BELOW NORMAL TEMPERATURES WILL BE COMMON THROUGH THE END OF THE  
WEEK ACROSS THE EASTERN PORTION OF THE FORECAST AREA, WHILE NEAR  
NORMAL READINGS WILL RETURN TO THE WESTERN DESERTS STARTING  
WEDNESDAY.  
 
- DRY CONDITIONS WILL PREVAIL FROM THURSDAY THOUGH EARLY NEXT WEEK  
AS HIGH PRESSURE TAKES HOLD ACROSS THE REGION.  
 

 
   
SHORT TERM /TODAY THROUGH WEDNESDAY/
 
 
AREAS OF LIGHT TO MODERATE RAINFALL WILL CONTINUE ACROSS PORTIONS OF  
THE REGION, MAINLY FOR SOUTHERN GILA, THROUGH THIS EVENING BEFORE  
THE MAJORITY OF THE SHOWER AND THUNDERSTORM ACTIVITY BEGINS TO PUSH  
OF OUT OF OUR FORECAST AREA. AS EXPECTED, RAINFALL TOTALS OVER THE  
PAST FEW DAYS HAVE VARIED GREATLY, WITH THE DRIEST SPOTS SEEING ONLY  
A FEW HUNDREDTHS OF AN INCH, WHILE MEASUREMENTS UPWARDS OF 2-2.5"  
HAVE BEEN SEEN SO FAR IN PARTS OF SOUTH-CENTRAL ARIZONA.  
ACCUMULATIONS WILL CONTINUE TO RISE FOR SOME AREAS, SO IT IS NOT OUT  
OF THE QUESTION THAT AREAS OF 3+", MAINLY CONFINED TO FOOTHILL AND  
HIGH TERRAIN AREAS, WILL BE SEEN ONCE THIS IS ALL SAID AND DONE.  
 
EVEN THOUGH MOST OF THE LOWER DESERT RAINFALL HAS MOVED ON, IT MAY  
NOT BE THE LAST OF SHOWER AND THUNDERSTORM ACTIVITY SEEN OVER THESE  
AREAS. WITH DRIER AIR SURGING BEHIND THE MAIN RAIN BANDS, NOTICEABLE  
CLEARING HAS TAKEN PLACE ACROSS MOST OF THE REGION. THIS DRY AIR  
ADVECTION WILL NOT COMPLETELY SCOUR OUT BOUNDARY-LAYER MOISTURE  
WHICH, COMBINED WITH DAY-TIME HEATING, SHOULD PROMOTE THE PRESENCE  
OF SOME DECENT CAPE UPWARDS OF 500-1000 J/KG. WITH THE BEST ASCENT  
ASSOCIATED WITH THE LOW REMOVED FROM OUR AREA AT THIS POINT, ANY  
CONVECTION THAT CAN POP WILL BE HEAVILY DEPENDENT ON OROGRAPHIC  
INFLUENCES. A SHARP GRADIENT OF 0-6KM SHEAR WILL BE LOCATED  
OVERHEAD, SO MAYBE SOME LONGER LIVED CELLS ARE BE OBSERVED, BUT THE  
MAJORITY SHOULD BE SHORT-LIVED DUE TO LACK OF MID AND UPPER-LEVEL  
SUPPORT/LIFT. EVEN WITH THE ENVIRONMENT, CONFIDENCE IN THIS ROUND OF  
ACTIVITY IS FAIRLY LOW AS CAMS HAVE BEEN INCONSISTENT RUN-TO-RUN ON  
WHERE IT PLACES THESE SHOWERS AND STORMS, WITH SOME KEEPING THEM  
WITHIN THE FLAGSTAFF CWA, WHILE OTHERS SHOW THE PHOENIX METRO AND  
EVEN AREAS AS FAR SOUTH AS THE I-8 CORRIDOR SEEING SOMETHING FORM.  
NONETHELESS, THE MAIN IMPACTS WILL BE BRIEF HEAVY DOWNPOURS, GUSTY  
WINDS, AND PERHAPS SOME ISOLATED INSTANCES OF SMALL HAIL IF STORMS  
CAN BECOME STRONG ENOUGH.  
 
TODAY SHOULD FEEL A BIT LIKE FALL ACROSS THE PORTIONS OF THE REGION  
AS HIGH TEMPERATURES WILL RUN A GOOD 15 DEGREES OR SO BELOW NORMAL  
ACROSS SOUTH-CENTRAL ARIZONA. READINGS FOR THE LOWER ELEVATIONS WILL  
RUN IN THE 70S AND LOW 80S, WHILE THE HIGHER ELEVATIONS WILL  
STRUGGLE TO GET OUT OF THE 60S. THE FURTHER WEST YOU GO, THE WARMER  
IT WILL BE AS SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA WILL REACH  
INTO THE MIDDLE 80S AND LOWER 90S, WHICH IS STILL A GOOD 4-8 DEGREES  
BELOW NORMAL.  
 
WEDNESDAY WILL BE A TRANSITION DAY AS THE PACIFIC LOW GRADUALLY  
EXITS THE REGION. SOME MORNING SCATTERED SHOWERS ARE LIKELY TO STILL  
BE ACROSS THE FAR EASTERN ARIZONA HIGH TERRAIN, BUT ANY ACTIVITY  
SHOULD QUICKLY WIND DOWN IN THE AFTERNOON. ELSEWHERE ON WEDNESDAY,  
SUNNY SKIES AND WARMER TEMPERATURES ARE FORECAST FOR SOUTHEAST  
CALIFORNIA AND SOUTHWEST ARIZONA WHILE THE SOUTH-CENTRAL ARIZONA  
LOWER DESERTS WILL SEE SOME LINGERING CLOUDS AND A CONTINUATION OF  
WELL BELOW NORMAL TEMPERATURES.  
 

 
   
LONG TERM /THURSDAY THROUGH WEDNESDAY/
 
 
MODEL GUIDANCE SHOWS UPPER LEVEL RIDGING FULLY MOVING INTO OUR  
REGION ON THURSDAY AND LIKELY STAYING PUT THROUGH THE UPCOMING  
WEEKEND. THIS WILL LEAD TO GRADUAL DRYING AND MOSTLY CLEAR SKIES  
WHILE TEMPERATURES SLOWLY RISE CLOSER TO THE NORMAL RANGE FOR THE  
SOUTH-CENTRAL ARIZONA LOWER DESERTS. THE WESTERN LOWER DESERTS MAY  
REACH 100 DEGREES AGAIN STARTING FRIDAY, BUT FOR THE EASTERN HALF OF  
ARIZONA SOME REINFORCING COOLER AIR FROM THE EAST FRIDAY THROUGH  
SATURDAY SHOULD KEEP DAYTIME HIGHS AT OR JUST ABOVE 90 DEGREES  
THROUGH SATURDAY. THIS COOLER EASTERLY FLOW MAY EVEN CONTINUE INTO  
EARLY NEXT WEEK WITH TEMPERATURES IN THE PHOENIX AREA STAYING RIGHT  
NEAR SEASONAL NORMALS FOR EARLY OCTOBER.  
 

 
   
AVIATION
 
UPDATED AT 2315Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
AREAS OF LOWER CIGS EARLY THIS EVENING AND UNCERTAINTY IN WIND  
SHIFTS/DIRECTIONS WILL BE THE MAIN WEATHER CONCERNS. LOWER CIGS WITH  
ISOLD SHRA/TSRA WILL BE COMMON JUST EAST OF THE TERMINALS THIS  
EVENING, THOUGH MOVING AWAY FROM THE METRO. W/SW WINDS WILL PREVAIL  
THROUGH EARLY EVENING WITH DECREASING CONFIDENCE IN TIMING OF A  
SHIFT TO EASTERLY COMPONENT MID EVENING. MIDLEVEL CLOUDS AND A FEW  
SHRA WILL SWEEP TOWARDS THE PHOENIX AREA OVERNIGHT, THOUGH SHOULD  
HAVE LITTLE TO NO IMPACT. WITH A FEW MID/HIGH CLOUD DECKS WEDNESDAY,  
VERY LOW CONFIDENCE EXISTS REGARDING WIND DIRECTIONS AS A LOW  
PRESSURE SYSTEM MAY SIT DIRECTLY ON THE PHOENIX METRO CREATING A  
WIDE VARIETY OF DIRECTIONS THROUGH THE AFTERNOON.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
GUSTY NORTH WINDS WITH ISOLD SHRA NEAR KBLH EARLY THIS EVENING WILL  
BE THE MAIN WEATHER CONCERN BEFORE MORE TRANQUIL CONDITIONS RETURN  
WEDNESDAY. GUSTS 20-30KT UNDER 8-10K FT AGL CIGS WILL BE COMMON INTO  
THE EARLY EVENING BEFORE SPEEDS WEAKEN AND CLOUD DECKS DISSIPATE  
THROUGH MID EVENING. CONFIDENCE IS VERY GOOD THAT CLEAR SKIES AND  
NEAR CALM WINDS WILL PREVAIL MUCH OF THE DAY WEDNESDAY.  
 

 
   
FIRE WEATHER
 
 
WIDESPREAD SHOWERS AND ISOLATED THUNDERSTORMS WILL AFFECT MUCH OF  
THE AREA EARLY TODAY BEFORE MAINLY AFFECTING THE ARIZONA HIGH  
TERRAIN THIS AFTERNOON AND EVENING. MODERATE TO HEAVY RAINFALL IS  
LIKELY TO IMPACT THE ARIZONA HIGH TERRAIN THROUGH AT LEAST EARLY  
AFTERNOON. HUMIDITIES WILL BEGIN TO TREND LOWER ACROSS THE WESTERN  
DISTRICTS LATER TODAY, BUT MORE SO ON WEDNESDAY. ELEVATED HUMIDITIES  
WILL PERSIST ACROSS THE EASTERN DISTRICTS THROUGH AT LEAST THURSDAY.  
WINDS WILL BE BREEZY TO LOCALLY WINDY AT TIMES TODAY BEFORE BECOMING  
LIGHT AGAIN ON WEDNESDAY. DRIER CONDITIONS AND NEAR TO SLIGHTLY  
ABOVE NORMAL TEMPERATURES ARE FORECAST FOR LATER THIS WEEK AND  
THROUGH THE WEEKEND.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...FLOOD WATCH UNTIL 9 PM MST THIS EVENING FOR AZZ547-556>558-  
560>563.  
 
CA...NONE.  
 

 
 

 
 
SHORT TERM...RW  
LONG TERM...KUHLMAN  
AVIATION...18  
FIRE WEATHER...KUHLMAN  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab AZ Page
The Nexlab CA Page Main Text Page