386  
FXUS65 KPSR 161934  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1234 PM MST THU OCT 16 2025  
 
   
KEY MESSAGES
 
 
- DRY AND TRANQUIL WEATHER CONDITIONS WITH ZERO RAIN CHANCES WILL  
PREVAIL THROUGH THE WEEKEND WITH TEMPERATURES REMAINING BELOW  
NORMAL.  
 
- TEMPERATURES WILL WARM BACK INTO THE NEAR NORMAL RANGE FOR EARLY  
NEXT WEEK WITH RAIN CHANCES POTENTIALLY RETURNING TO AT LEAST  
THE ARIZONA HIGH TERRAIN DURING THE MIDDLE OF NEXT WEEK.  
 

 
   
SHORT TERM /TODAY THROUGH SATURDAY/
 
 
EARLY AFTERNOON WATER VAPOR SATELLITE IMAGERY SHOWS THE UPPER-  
LEVEL TROUGH THAT BROUGHT ACTIVE WEATHER TO PORTIONS OF THE  
WESTERN CONUS EARLIER THIS WEEK SITUATED OVER THE NORTHERN ROCKIES  
WITH THE DESERT SOUTHWEST UNDER CONTINUED CYCLONIC FLOW ALOFT.  
WESTERLY FLOW ALOFT CONTINUES TO ADVECT A DRY AIR MASS INTO THE  
REGION WITH PWATS NOW BELOW 0.5", THUS DRY AND TRANQUIL CONDITIONS  
WITH MOSTLY CLEAR SKIES WILL PREVAIL INTO THE WEEKEND. THE BELOW  
NORMAL HEIGHT ANOMALIES WILL CONTINUE TO KEEP TEMPERATURES A GOOD  
5-8 DEGREES BELOW NORMAL THROUGH FRIDAY WITH AFTERNOON HIGHS  
TOPPING OUT IN THE LOW TO MID 80S ACROSS THE LOWER DESERTS WITH  
EARLY MORNING LOWS BOTTOMING OUT IN THE 50S ACROSS MOST AREAS. BY  
SATURDAY, AN UPPER-LEVEL RIDGE WILL BEGIN TO BUILD OVER THE REGION  
AS AN UPPER-LEVEL TROUGH BUILDS OFF THE COAST OF THE NORTHERN  
BAJA PENINSULA, MARKING THE BEGINNING OF A WARMING TREND.  
 

 
   
LONG TERM /SUNDAY THROUGH WEDNESDAY/
 
 
THE FIRST PART OF NEXT WEEK SHOULD SEE A WEAK RIDGE EXTENDING FROM  
CENTRAL CALIFORNIA THROUGH THE DESERT SOUTHWEST, WHILE THE TROUGH  
ENERGY THAT SINKS TO OUR SOUTHWEST EARLIER IN THE WEEKEND FORMS A  
CUT-OFF LOW. MODELS ARE IN GOOD AGREEMENT WITH THIS CUT-OFF LOW  
FORMATION AND EVENTUALLY DRIFTING IT BACK TO THE NORTH NORTHEAST  
TOWARD SOUTHERN CALIFORNIA BY AROUND NEXT TUESDAY/WEDNESDAY. THE  
RIDGING OVER OUR REGION EARLY NEXT WEEK IS EXPECTED TO PUSH  
TEMPERATURES BACK INTO THE NORMAL RANGE WITH HIGHS IN THE MID TO  
UPPER 80S ACROSS THE LOWER DESERTS SUNDAY AND MONDAY BEFORE  
BEGINNING TO COOL AGAIN AS EARLY AS TUESDAY.  
 
WHERE MODELS BEGIN TO DIVERGE IS SEEN WITHIN MOISTURE FIELDS AS  
THE CUT-OFF APPROACHES OUR REGION. BOTH THE GEFS AND EPS DO  
SHOWING MOISTURE INCREASING TUESDAY INTO WEDNESDAY, BUT THE GEFS  
ONLY SHOWS PWATS RETURNING TO 100-110% OF NORMAL ACROSS EASTERN  
AND CENTRAL ARIZONA WHEREAS THE EPS SHOWS PWATS INCREASING TO  
150-170% OF NORMAL. THIS DISCREPANCY IS FAIRLY SIGNIFICANT AND  
IS LEADING TO HIGH UNCERTAINTY IN POPS FOR THE MIDDLE OF NEXT  
WEEK. IF THE SYSTEM IS CLOSER TO THE GEFS SOLUTION, THEN ANY RAIN  
CHANCES SHOULD MOSTLY BE ACROSS ARIZONA HIGH TERRAIN AREAS, WHILE  
THE EPS WOULD HAVE CHANCES EASILY EXTENDING INTO AT LEAST THE  
SOUTH-CENTRAL ARIZONA LOWER DESERTS. EITHER WAY, POTENTIAL  
RAINFALL AMOUNTS ARE EXPECTED TO BE ON THE LIGHTER SIDE. BOTH  
ENSEMBLE SUITES EVENTUALLY SHOW THE CUT-OFF LOW QUICKLY WEAKENING  
AS IT MOVES NORTHEASTWARD THROUGH OUR REGION AROUND NEXT WEDNESDAY  
AND THURSDAY. THE WEATHER SYSTEM MAY ALSO LEAD TO A BRIEF DIP IN  
TEMPERATURES DURING THE MIDDLE PART OF NEXT WEEK, BUT FOR NOW THEY  
ARE NOT LIKELY TO FALL MUCH BELOW NORMAL.  
 

 
   
AVIATION
 
UPDATED AT 1700Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT; AND  
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION CONCERNS ARE ANTICIPATED THROUGH FRIDAY AFTERNOON  
UNDER CLEAR SKIES. LIGHT WINDS (AOB 6 KTS) WILL PREVAIL, GENERALLY  
FOLLOWING DIURNAL TENDENCIES ACROSS THE GREATER PHOENIX AREA, WITH  
PERIODS OF VARIABLE TO NEARLY CALM CONDITIONS. WIND DIRECTIONS  
WILL VARY BETWEEN NORTH AND WEST AT KIPL AND KBLH.  
 

 
   
FIRE WEATHER
 
 
DRY, TRANQUIL WEATHER WITH BELOW NORMAL TEMPERATURES WILL PREVAIL  
THROUGH THE END OF THE WEEK. MINIMUM AFTERNOON HUMIDITY LEVELS  
WILL GENERALLY FALL INTO A 15-25% RANGE ACROSS THE LOWER DESERTS  
TO UPWARDS OF 30-35% OVER THE EASTERN ARIZONA HIGH TERRAIN.  
OVERNIGHT RECOVERY WILL BE GOOD TO EXCELLENT. LIGHT DIURNAL WINDS  
ARE EXPECTED ACROSS THE EASTERN DISTRICTS, WHILE SOME OCCASIONAL  
BREEZY NORTHERLY WINDS WILL BE SEEN ACROSS THE WESTERN DISTRICTS.  
SIMILAR WEATHER CONDITIONS ARE LIKELY TO PERSIST FOR THE FIRST  
PART OF NEXT WEEK WITH TEMPERATURES RETURNING TO NORMAL.  
 

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

 
 

 
 
SHORT TERM...LOJERO  
LONG TERM...KUHLMAN  
AVIATION...WHITTOCK  
FIRE WEATHER...KUHLMAN  
 
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