567  
FXUS65 KPSR 042202  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
302 PM MST SAT OCT 4 2025  
   
KEY MESSAGES
 
 
- A DRY COLD FRONT MOVING THROUGH THE REGION THIS MORNING WILL  
CAUSE TEMPERATURES TO GO BELOW NORMAL THIS WEEKEND.  
 
- A GRADUAL WARMING TREND WILL COMMENCE ONCE AGAIN FOR THE FIRST  
HALF OF NEXT WEEK.  
 
- INCREASING RAIN CHANCES LATE NEXT WEEK INTO NEXT WEEKEND WITH  
AT LEAST A LOW CHANCE FOR IMPACTFUL FLOODING RAINFALL POSSIBLE,  
BUT FORECAST CONFIDENCE REMAINS LOW AT THIS TIME.  
 

 
   
SHORT TERM /TODAY THROUGH MONDAY/
 
 
BENIGN AND FAIRLY SEASONAL WEATHER IS EXPECTED THE REST OF THIS  
WEEKEND AND THE BEGINNING OF THE COMING WORK WEEK. THE SHORTWAVE  
TROUGH WHICH HAS BROUGHT DRIER, COOLER, AND BREEZIER CONDITIONS TO  
THE REGION IS SEEN ON SATELLITE LIFTING INTO WYOMING THIS  
AFTERNOON. A LONG-WAVE TROUGH STILL REMAINS IN PLACE ACROSS MUCH  
OF THE WEST. THIS LONG-WAVE TROUGH, AND THE DRIER AIR BROUGHT IN,  
WILL HELP KEEP TEMPERATURES ON THE COOLER SIDE THE NEXT FEW DAYS.  
HIGH TEMPERATURES THIS AFTERNOON ARE FORECAST TO REACH THE MID-80S  
TO 90 DEGREES ACROSS THE LOWER DESERTS. LOW TEMPERATURES THIS  
MORNING WERE MOSTLY IN THE 60S. SIMILAR MORNING AND AFTERNOON  
TEMPERATURES ARE EXPECTED AGAIN TOMORROW. SO, OVERALL A VERY NICE  
WEEKEND TEMPERATURE-WISE. HOWEVER, CONTINUE TO EXERCISE CAUTION IN  
THE HEART OF THE AFTERNOONS, AS LONG EXPOSURE TO THE HEAT WITHOUT  
BREAKS OR PROTECTION CAN LEAD TO NEGATIVE HEALTH IMPACTS. ASIDE  
FROM THE BELOW NORMAL TEMPERATURES, BREEZY CONDITIONS WILL  
CONTINUE THIS AFTERNOON, PRIMARILY FOR SOUTHERN GILA COUNTY, WITH  
PEAK GUSTS UP TO 20-30 MPH. LIGHTER WINDS ARE EXPECTED TOMORROW.  
TEMPERATURES WARM A FEW DEGREES MONDAY, AS 500MB HEIGHTS START TO  
RISE, AND WINDS WILL REMAIN LIGHT.  
 

 
   
LONG TERM /TUESDAY THROUGH SATURDAY/
 
 
THE HIGHLIGHT OF THE LONG TERM FORECAST CONTINUES TO BE THE  
POTENTIAL FOR ANOTHER HIGH IMPACT RAIN EVENT WITH TROPICAL  
INFLUENCES LATE NEXT WEEK. NEWLY NAMED TROPICAL STORM PRISCILLA,  
OFF THE SOUTHERN COAST OF MEXICO, IN THE EASTERN PACIFIC, IS  
FORECAST TO SLOWLY DRIFT NORTHWEST THROUGH THE MIDDLE OF THE  
COMING WEEK. BEYOND THIS THERE IS STILL A LOT OF UNCERTAINTY IN  
WHAT WILL UNFOLD FOR THE DESERT SOUTHWEST. THE ONLY COUPLE OF  
CERTAINTIES THERE SEEMS TO BE AT THIS TIME IS THAT THERE WILL BE  
AN INCREASE IN ANOMALOUS MOISTURE INTO THE SOUTHWEST U.S. AND THAT  
PRISCILLA WILL LIKELY FALL APART AT SEA AS IT MOVES CLOSER TO  
HIGHER SHEAR AROUND THE BASE OF THE LINGERING TROUGH PATTERN OVER  
THE NORTHEASTERN PACIFIC AND ALONG THE WEST COAST. THERE IS STILL  
THE QUESTION OF WHETHER THE REMNANTS OF THE CYCLONE WILL TURN  
RIGHT, AND BE PULLED NORTHEASTWARD BY THE TROUGH, UP INTO THE  
SOUTHWEST CONUS, STALL AND FIZZLE OUT, OR TURN WESTWARD FURTHER  
OUT TO SEA. THERE ARE STILL SEVERAL ECMWF ENSEMBLE MEMBERS  
FAVORING THE REMNANTS MOVING NORTHEAST INTO THE SOUTHWEST,  
INCLUDING THE DETERMINISTIC, WHILE THE MAJORITY OF GEFS AND GEPS  
TURN THE REMNANTS WEST FURTHER OUT TO SEA. WHILE THERE IS GOOD  
CONFIDENCE IN ANOMALOUS MOISTURE BEING PULLED NORTHWARD, THE  
REMNANTS OF THE CYCLONE MAY BE NEEDED TO PROVIDE A SOURCE OF LIFT  
IN THE REGION, AS RIGHT NOW MODELS ARE NOT SHOWING TOO MUCH IN  
THE WAS OF INSTABILITY LATE WEEK AND INTO THE WEEKEND AND THE  
BETTER UPPER LEVEL JET FORCING MAY STAY FURTHER WEST AND NORTH,  
FAVORING NORTHERN AND WESTERN AZ AND POINTS NORTH AND WEST, AT  
LEAST FOR THE FRIDAY TIME PERIOD.  
 
IT IS STILL WORTH TALKING ABOUT THIS, DESPITE BEING AROUND A WEEK  
OUT AND LOW CONFIDENCE/LOW PROBABILITY, DUE TO THE POTENTIAL HIGH  
IMPACT, ESPECIALLY AFTER LAST WEEK'S HIGH IMPACT FLOODING AND  
WINDS. THERE ARE MODEL SOLUTIONS WITH HIGH RAINFALL AMOUNTS FOR  
SOUTHERN AZ AND SOCAL. THE OVERALL SPREAD IN MODEL QPF IS STILL  
QUITE LARGE, ALTHOUGH THERE HAS BEEN A SLIGHT BACKING OFF ON THE  
NUMBER OF SOLUTIONS WITH EXTREME RAINFALL AMOUNTS. THERE ARE  
STILL A FEW MEMBERS MEMBERS (10-15% OF ALL MEMBERS) WITH 1.5-2.5+  
INCHES OF STORM TOTAL RAINFALL IN PARTS OF THE REGION, INCLUDING  
PHOENIX. THERE IS ALSO AROUND 25% OF MEMBERS WITH NO RAINFALL  
ACCUMULATION. MANY OF THE DRIER MEMBERS INVOLVE 1) THE TROPICAL  
REMNANTS STAYING OUT AT SEA AND 2) A STRONGER HIGH PRESSURE MOVING  
IN FROM THE SOUTHEAST. WHILE A STRONGER RIDGING SCENARIO DOESN'T  
LOOK TO DECREASE PWATS OVER OUR AREA IT WOULD PUSH THE THE BETTER  
FORCING (THE COASTAL TROUGH AND REMNANTS OF THE TROPICAL SYSTEM)  
FURTHER WEST.  
 
TIMING-WISE, THE WINDOW FOR RAINFALL IS STILL PRETTY LARGE, AND  
THERE WILL LIKELY BE MULTIPLE DAYS WITH RAIN, BUT BEST TIMING  
STILL LOOKS LIKE FRIDAY-MONDAY. HOWEVER, SOME MEMBERS STILL SHOW  
RAINFALL AS EARLY AS THURSDAY, WITH THE INITIAL PUSH OF MOISTURE  
INTO THE REGION. ULTIMATELY, IT IS GOOD TO BE AWARE OF THE  
POTENTIAL FOR ANOTHER HIGH IMPACT RAIN EVENT IN 6-12 DAY FORECAST.  
 
PRIOR TO THE RAIN CHANCES FOR LATE NEXT WEEK THE WEATHER WILL REMAIN  
RATHER CALM. DRY CONDITIONS WITH GRADUALLY WARMING TEMPERATURES ARE  
EXPECTED FOR THE FIRST HALF OF NEXT WEEK. WITH TEMPERATURES WARMING  
BACK TO NEAR TO SLIGHTLY ABOVE NORMAL ACROSS SE CA AND SW AZ AND  
SEVERAL DEGREES ABOVE NORMAL ACROSS SOUTH-CENTRAL AND EASTERN AZ BY  
WEDNESDAY. MORNING LOW TEMPERATURES WILL ALSO GRADUALLY WARM, BUT  
WILL REMAIN NEAR TO SLIGHTLY ABOVE SEASONAL LEVELS. BY THE END OF  
NEXT WEEK AND HEADING INTO NEXT WEEKEND, THE TEMPERATURE FORECAST  
ALSO BECOMES UNCERTAIN, JUST LIKE THE UNCERTAINTY IN THE  
PRECIPITATION FORECAST. IQR SPREADS ARE CURRENTLY AROUND 6-12  
DEGREES. DESPITE THE UNCERTAINTY IT DOES LOOK LIKE TEMPERATURES WILL  
START TO COOL NEXT WEEKEND, THE QUESTION IS HOW COOL WILL THEY GO.  
 

 
   
AVIATION
 
UPDATED AT 1728Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION CONCERNS THROUGH THE TAF PERIOD WITH WIND SPEEDS AT  
ALL TERMINALS AOB 10KTS. AT KPHX, WESTERLY WINDS WILL PREVAIL  
THROUGH THE AFTERNOON/EVENING BEFORE GOING E'RLY FOR THE OVERNIGHT  
HOURS. SKIES WILL CONTINUE TO REMAIN MOSTLY CLEAR.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
WINDS AT BOTH TERMINALS WILL FAVOR A WESTERLY COMPONENT, SWITCHING  
BETWEEN W'RLY AND NW'RLY DURING THE PERIOD. WIND SPEEDS WILL BE  
AOB 10 KT. CLEAR SKIES WILL CONTINUE.  
 

 
   
FIRE WEATHER
 
 
DRY CONDITIONS WITH NO CHANCES FOR RAIN ARE EXPECTED TODAY THROUGH  
AT LEAST WEDNESDAY. TEMPERATURES ARE BELOW NORMAL NOW, BUT WILL  
WARM DURING THE UPCOMING WEEK, BACK TO NORMAL TO SLIGHTLY ABOVE  
NORMAL AS EARLY AS MONDAY OR TUESDAY. BREEZY CONDITIONS THIS  
AFTERNOON WILL MOSTLY FOCUS ACROSS SOUTHERN GILA COUNTY, WITH  
WESTERLY GUSTS UP TO 20-30 MPH. LIGHTER WINDS ARE EXPECTED ACROSS  
ALL DISTRICTS TOMORROW THROUGH EARLY WEEK. DAILY MINRHS OF 12-20%  
WILL CONTINUE THROUGH WEDNESDAY, WITH OVERNIGHT RECOVERIES OF  
30-50%. THERE ARE INCREASING CHANCES FOR WETTING RAINFALL BY THE  
END OF NEXT WEEK, HOWEVER, BETTER CHANCES EXIST FOR NEXT WEEKEND  
AND FORECAST CONFIDENCE REMAINS LOW. HOWEVER, THERE IS AT LEAST  
HIGH CONFIDENCE THAT THERE WILL BE AN INCREASE IN MOISTURE BY THE  
END OF NEXT WEEK PUSHING MINRHS INTO THE 20-30% RANGE WITH  
OVERNIGHT RECOVERIES OF 45-65%.  
 

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

 
 

 
 
SHORT TERM...BENEDICT  
LONG TERM...BERISLAVICH/BENEDICT  
AVIATION...BERISLAVICH/RYAN  
FIRE WEATHER...BENEDICT  
 
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