446  
FXUS65 KPSR 041700  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1000 AM MST TUE NOV 4 2025  
   
UPDATE  
 
UPDATED AVIATION  
 
 
   
KEY MESSAGES  
 
- DRY AND TRANQUIL WEATHER WILL PREVAIL ACROSS THE DESERT SOUTHWEST  
THIS WEEK.  
 
- HIGH TEMPERATURES ACROSS THE LOWER DESERTS ARE EXPECTED TO SLOWLY  
COOL FROM AROUND 90 DEGREES TODAY TO THE MID 80S BY THE THURSDAY.  
 
 
   
SHORT TERM /TODAY THROUGH WEDNESDAY/  
 
THE WEATHER PATTERN CONTINUES TO SUPPORT FAIRLY ZONAL WESTERLY FLOW  
ACROSS THE BULK OF THE CONUS WITH A FLATTENED RIDGE CURRENTLY  
CENTERED OVER TEXAS. THIS RIDGE WILL CONTINUE TO BE THE DOMINANT  
WEATHER FEATURE FOR OUR REGION, KEEPING HEIGHTS ALOFT ABOVE  
CLIMATOLOGICAL NORMALS THROUGH WEDNESDAY. THE ATMOSPHERE IS ALSO  
QUITE DRY ACROSS THE DESERT SOUTHWEST WITH PWATS HOVERING AROUND 75%  
OF NORMAL. AS FAR AS WHAT THAT TRANSLATES TO FOR WEATHER CONDITIONS,  
IT WILL BE MUCH OF THE SAME THROUGH WEDNESDAY WITH GENERALLY CLEAR  
SKIES AND HIGH TEMPERATURES NEAR 90 DEGREES, OR 5-8 DEGREES ABOVE  
NORMAL.  
 
 
   
LONG TERM /THURSDAY THROUGH NEXT WEEK/  
 
FOR LATE THIS WEEK AND THROUGH AT LEAST EARLY NEXT WEEK, VERY LITTLE  
WILL CHANGE. INITIALLY, A PASSING TROUGH WELL TO OUR NORTH WILL AT  
LEAST SUPPRESS THE RIDGE IN PLACE LOWERING H5 HEIGHTS FROM THE  
CURRENT 587-589DM TO 584-586DM BY THURSDAY. THE RIDGE IS ALSO  
FORECAST TO SHIFT ITS HIGH CENTER TO OFF THE COAST OF SOUTHERN  
CALIFORNIA. THE BRIEF DIP IN HEIGHTS WILL HELP TO BRING TEMPERATURES  
DOWN A FEW DEGREES STARTING THURSDAY AS HIGHS ARE FORECAST TO DROP  
TO BETWEEN 83-86 DEGREES. HOWEVER, THIS WILL NOT LAST VERY LONG AS  
THE RIDGE NOW CENTERED TO OUR SOUTHWEST IS EXPECTED TO EVENTUALLY  
MOVE OVER OUR REGION THIS WEEKEND. AS A RESULT, TEMPERATURES WILL  
GRADUALLY CREEP BACK TOWARD THE 90 DEGREE MARK BY SUNDAY OR MONDAY.  
 
MODEL UNCERTAINTY BEGINS TO INCREASE SUBSTANTIALLY BY THE MIDDLE  
OF NEXT WEEK AS ENSEMBLES GENERALLY FAVOR AN UPPER LEVEL LOW  
DEVELOPING WEST OF CALIFORNIA BY MONDAY BEFORE POTENTIALLY  
SWINGING THROUGH PORTIONS OF OUR REGION BY AROUND NEXT WEDNESDAY.  
THIS FIRST WEATHER FEATURE WILL LIKELY BE ON THE DRIER SIDE AND  
NOT BRING MUCH IN THE WAY OF PRECIPITATION CHANCES, BUT A  
POTENTIAL SECOND FOLLOW-ON SYSTEM MAY BE DIFFERENT. UNCERTAINTY IS  
QUITE HIGH FOR THE SECOND SYSTEM LATER NEXT WEEK AS IT COULD END  
UP BECOMING CUT OFF FROM THE MAIN FLOW AND STAY TO OUR WEST, OR IT  
COULD MOVE ON THROUGH SHORTLY AFTER THE FIRST SYSTEM. MODELS DO  
AT LEAST INDICATE A MUCH BETTER CHANCE OF BETTER MOISTURE  
ASSOCIATED WITH THE SECOND SYSTEM. FOR NOW, GUIDANCE SHOWS MODEST  
RAIN CHANCES FOR A GOOD PORTION OF ARIZONA BY AROUND NEXT  
FRIDAY/SATURDAY TIMEFRAME WITH TEMPERATURES FALLING BACK CLOSER TO  
THE NORMAL RANGE.  
 
 
   
AVIATION  
UPDATED AT 1700Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT; AND  
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
NO WEATHER ISSUES SHOULD EXIST THROUGH WEDNESDAY AFTERNOON UNDER A  
FEW HIGH CIRRUS DECKS. WINDS WILL BEHAVE SIMILARLY TO THE PAST 24  
HOURS INCLUDING SPEEDS UNDER 10KT AND THE LIKELIHOOD OF DIRECTIONS  
NEVER FULLY ACHIEVING AN AFTERNOON WESTERLY FETCH AROUND THE PHX  
TERMINALS, BUT RATHER OBTAINING ONLY A LIGHT AND VARIABLE CHARACTER  
FOR A FEW HOURS AROUND SUNSET.  
 
 
   
FIRE WEATHER  
 
ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS WILL PREVAIL THROUGH  
THIS WEEK. MINIMUM HUMIDITY LEVELS AROUND 15% MIDWEEK WILL RISE  
CLOSER TO 20% LATER IN THE WEEK WITH FAIR OVERNIGHT RECOVERIES OF 30-  
50%. WINDS WILL BE LIGHT, GENERALLY 15 MPH OR LESS, AND WILL TEND TO  
FOLLOW A TYPICAL DIURNAL UPSLOPE/NOCTURNAL DRAINAGE PATTERN WITH  
LIMITED AFTERNOON GUSTINESS.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
 
SHORT TERM...KUHLMAN  
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