278  
FXUS65 KPSR 100540  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1040 PM MST FRI OCT 9 2026  
   
UPDATE  
 
UPDATED AVIATION  
 
 
   
KEY MESSAGES  
 
- AN UNSETTLED WEATHER PATTERN WITH A PERIOD REMNANT TROPICAL  
MOISTURE WILL SETTLE ACROSS THE REGION THIS WEEKEND THROUGH EARLY  
NEXT WEEK WITH TEMPERATURES COOLING BELOW NORMAL.  
 
- STRONG, GUSTY WINDS WILL IMPACT THE REGION SUNDAY WITH WIDESPREAD  
WIND ADVISORIES IN PLACE AS A RESULT OF GUSTS 35 TO 55 MPH.  
 
- NUMEROUS SHOWERS AND EMBEDDED THUNDERSTORMS WILL PERIODICALLY  
IMPACT THE AREA OVER THE NEXT SEVERAL DAYS WITH BRIEF, HEAVY  
DOWNPOURS.  
 
- WEATHER CONDITIONS WILL DRY DURING THE MIDDLE OF NEXT WEEK WITH  
TEMPERATURES REBOUNDING CLOSER TO NORMAL.  
 
 
   
SHORT TERM /TODAY THROUGH SATURDAY/  
 
FAIRLY QUIET CONDITIONS WILL ROUND OUT THE WORK WEEK BEFORE SEVERAL  
WEATHER SYSTEMS INTERACT TO BRING UNSETTLED AND REGIONALLY IMPACTFUL  
RAIN, WIND, AND SEVERE WEATHER POTENTIAL OVER THE WEEKEND. TODAY,  
THE INFLUENCE OF BROAD ANTICYCLONIC FLOW REMAINS OVER THE DESERT  
SOUTHWEST, WITH H5 HEIGHTS ANALYZED BETWEEN 584-586 DAM AT THIS  
HOUR. THOUGH HEIGHTS ARE GRADUALLY ERODING TODAY, THERMAL PROFILES  
HAVE YET TO RESPOND MEANINGFULLY, AND THUS 850 MB TEMPERATURES  
UPWARDS OF 24C-26C (ABOVE THE 90TH PERCENTILE OF CLIMATOLOGY) WILL  
CONTINUE TO SUPPORT HIGHS AROUND 10F ABOVE DAILY NORMALS. YUMA AND  
EL CENTRO WILL ONCE AGAIN BE WITHIN A COUPLE OF DEGREES OF DAILY  
RECORDS, WITH AREAS OF MAJOR HEATRISK STILL CONTINUING. THEREFORE,  
EXTREME HEAT WARNINGS REMAIN IN EFFECT FOR THE IMPERIAL VALLEY AND  
YUMA AREAS THROUGH THIS EVENING.  
 
OVER THE EASTERN PACIFIC, TROPICAL STORM RACHEL AND A SUBTROPICAL  
SHORTWAVE/CUTOFF LOW HAVE BEGUN TO INTERACT WELL OFFSHORE THE  
NORTHERN BAJA PENINSULA, TURNING THE TROPICAL SYSTEM'S TRACK  
NORTHEASTWARD. SOUTH SOUTHWESTERLY MOIST FLOW WILL INCREASE IN  
EARNEST SATURDAY AND ESPECIALLY BY SATURDAY NIGHT, WITH NAEFS MEAN  
IVT NEAR/EXCEEDING CLIMATOLOGICAL MAXIMUM FOR THIS TIME OF YEAR.  
MOISTURE AND UPPER LEVEL SUPPORT ARE LIKELY TO PEAK SATURDAY  
NIGHT/EARLY SUNDAY MORNING AS THE REMNANTS OF RACHEL QUICKLY EJECT  
NORTHEASTWARD NEAR/ALONG THE LOWER COLORADO RIVER, RESULTING IN THE  
MOST WIDESPREAD COVERAGE OF SHOWERS AND STORMS. HOWEVER, BEFORE THE  
PEAK TIMING FOR RAIN CHANCES, SCATTERED SHOWERS AND THUNDERSTORMS  
ARE EXPECTED TO ERUPT AS EARLY AS LATE SATURDAY MORNING/SATURDAY  
AFTERNOON. STRONG, GUSTY WINDS AND LOCALIZED HEAVY RAINFALL REMAIN  
THE MAIN THREATS WITH THIS INITIAL ACTIVITY. SPC HAS ISSUED A  
MARGINAL RISK FOR SEVERE STORMS SATURDAY INTO EARLY SUNDAY MORNING,  
AND INDICATES AT LEAST A VERY LOW CHANCE FOR A TORNADO OR TWO. THE  
STRENGTHENING WIND FIELDS DO SUPPORT THIS, WITH GFS BUFR SOUNDINGS  
ALSO SHOWING A BRIEF WINDOW WITH HIGHER MUCAPE (UPWARDS OF 500-1000  
J/KG), EBWD 30-40 KTS, SFC-1 KM SHEAR ABOVE 10 KTS, AND LCLS  
LOWERING BELOW 2000 M. SUPERCELLULAR STORMS MODES DO LOOK LIKE THEY  
WILL BE SUPPORTED BY THE ENVIRONMENT, AT LEAST FOR A TEMPORARY  
WINDOW OF TIME SATURDAY NIGHT INTO SUNDAY MORNING. HOWEVER, IT IS  
IMPORTANT TO KEEP IN MIND THIS IS A HIGHLY VOLATILE FORECAST, WITH  
SMALL UPSTREAM CHANGES RESULTING IN LARGE DOWNSTREAM FORECAST  
SHIFTS. REGARDLESS, WITH ANY ORGANIZED STORM MODES THAT DEVELOP  
SATURDAY PM INTO SUNDAY, THE PRIMARY AND MORE WIDESPREAD THREAT WILL  
BE FOR DAMAGING WIND GUSTS.  
 
 
   
LONG TERM /SUNDAY THROUGH THURSDAY/  
 
THE MORE IMPACTFUL WEATHER IS EXPECTED ON SUNDAY AS THE REMNANTS OF  
RACHEL MOVE THROUGH. ACCORDING TO THE LATEST OFFICIAL FORECAST TRACK  
FROM THE NATIONAL HURRICANE CENTER, RACHEL IS EXPECTED TO ACCELERATE  
NORTH-NORTHEASTWARD ALONG THE VICINITY OF THE LOWER COLORADO RIVER  
VALLEY. AN AREA OF HEAVY RAINFALL IS LIKELY TO FOLLOW ALONG AND JUST  
TO THE WEST OF WHERE RACHEL TRACKS. EVEN THOUGH THE OFFICIAL NHC  
FORECAST HAS THE SYSTEM TRACKING ALONG THE VICINITY OF THE LOWER  
COLORADO RIVER VALLEY SUGGESTING THAT THE HEAVY RAINFALL MAY FALL  
ACROSS PORTIONS OF SOUTHEAST CA, THERE IS A LOT OF SPREAD AMONGST  
THE GUIDANCE IN THE TRACK AS SOME SOLUTIONS HAVE RACHEL TRACKING  
NEAR THE SOUTHERN CA COAST WHEREAS OTHER SOLUTIONS HAVE THE SYSTEM  
TRACKING AS FAR EAST AS SOUTHWEST AZ. THEREFORE, THE RAINFALL  
FORECAST IS STILL HIGHLY VOLATILE AND COULD STILL SIGNIFICANTLY  
SHIFT DEPENDING ON THE EVENTUAL TRACK. THE GREATER IMPACT WITH  
RACHEL WILL BE THE POTENTIAL FOR STRONG WINDS AS A BELT OF STRONG  
850 MB WINDS IN EXCESS OF 40-50 KTS IS LIKELY TO SET UP ALONG THE  
EASTERN QUADRANT OF RACHEL WITH MUCH OF THE GUIDANCE SHOWING GUSTS  
EXCEEDING 40-50 MPH ACROSS MUCH OF SOUTHWEST INTO SOUTH-CENTRAL AZ,  
ESPECIALLY EARLY SUNDAY MORNING THROUGH SUNDAY AFTERNOON. WIND GUSTS  
THIS HIGH COULD CERTAINLY RESULT IN AREAS OF BLOWING DUST ACROSS THE  
DUST PRONE AREAS. GIVEN THE STRONG WIND POTENTIAL, A WIND ADVISORY  
HAS BEEN HOISTED FROM EASTERN RIVERSIDE AND IMPERIAL COUNTIES  
THROUGH ALL OF SOUTHWEST AND SOUTH-CENTRAL AZ. IN ADDITION TO THE  
WIND THREAT, THERE WILL ALSO BE THE POTENTIAL ALONG THE EASTERN  
QUADRANT FOR MULTIPLE ROUNDS OF WIDELY SCATTERED SHOWERS AND STORMS  
TO MATERIALIZE. THERE IS A POTENTIAL FOR SOME OF THESE STORMS TO  
REACH SEVERE LEVELS GIVEN THAT STRONG VERTICAL SHEAR IN EXCESS OF 50  
KTS WILL BE PRESENT, HOWEVER, THE SEVERE POTENTIAL WILL BE DEPENDENT  
ON HOW MUCH INSTABILITY WILL BE PRESENT.  
 
EVEN THOUGH THE REMNANTS OF RACHEL WILL BE WELL NORTH OF THE AREA BY  
SUNDAY EVENING, UNSETTLED CONDITIONS WILL CONTINUE RIGHT THROUGH  
EARLY NEXT WEEK AS THE MAIN WEST COAST TROUGH MOVES THROUGH THE  
REGION BRINGING ADDITIONAL CHANCES FOR SHOWERS AND ISOLATED  
THUNDERSTORMS, WITH THE HIGHEST CHANCES ACROSS THE FOOTHILLS AND  
HIGHER TERRAIN AREAS TO THE NORTH AND EAST OF PHOENIX FROM UPSLOPE  
FLOW. THEREAFTER, DRIER AND QUIETER WEATHER IS EXPECTED BY THE  
MIDDLE OF THE WEEK AS THE MAIN TROUGH AXIS LIFTS TO THE NORTHEAST.  
 
UNDER THE PRESENCE OF THE TROUGHING PATTERN, WELL-BELOW NORMAL  
TEMPERATURES ARE EXPECTED DURING THE FIRST HALF OF NEXT WEEK WITH  
LOWER DESERTS HIGHS GOING FROM THE LOW TO MID 80S ON SUNDAY TO  
MOSTLY 70S TUESDAY AND WEDNESDAY. EARLY MORNING LOWS WILL ALSO TAKE  
A TUMBLE WITH THE COOLEST MORNING EXPECTED ON WEDNESDAY AS  
TEMPERATURES ARE EXPECTED TO BOTTOM OUT IN THE 50S ACROSS MUCH OF  
THE REGION WITH EVEN SOME 40S ACROSS THE HIGHER TERRAIN AREAS.  
 
 
   
AVIATION  
UPDATED AT 0540Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
THE PRIMARY WEATHER ISSUES WILL BE SHRA AND POTENTIALLY EMBEDDED  
TSRA ENTERING THE PHOENIX METRO SATURDAY AFTERNOON AND EVENING, AND  
SUBSEQUENT THE EFFECT ON WINDS AS MIDLEVEL CIGS DEVELOP AND LOWER.  
CONFIDENCE IS GOOD THAT E/SE WINDS WILL PREVAIL THROUGH SATURDAY  
MORNING AS 10-15K FT AGL CIGS FILL IN ACROSS THE AREA. SCATTERED  
SHRA SHOULD ENTER THE WESTERN PORTIONS OF THE METRO EARLY SATURDAY  
AFTERNOON, AND MAY ALLOW WINDS TO SHIFT TO A W/SW DIRECTION.  
COVERAGE OF SHRA APPEARS LOW ENOUGH TO PRECLUDE A PREDOMINANT  
MENTION, AND WILL ADVERTISE A PROLONGED PERIOD OF VCSH. A FEW  
EMBEDDED TSRA WILL ALSO BE POSSIBLE HEADING INTO THE EVENING, BUT  
ODDS ONLY JUSTIFY A PROB30 MENTION AT THIS TIME WITH POTENTIALLY  
ERRATIC, GUSTY WINDS. CONFIDENCE IS BETTER THAT AN EAST COMPONENT  
WILL SETTLE BACK INTO THE AREA SATURDAY NIGHT, AND HAVE KEPT A VCSH  
MENTION THOUGH ITS MORE UNCERTAIN HOW EXPANSIVE SHRA WILL BE.  
 
SUNDAY OUTLOOK: HIGH IMPACT WEATHER STILL APPEARS TO BE ARRIVING AT  
ALL TERMINALS SUNDAY MID/LATE MORNING THROUGH THE AFTERNOON.  
SHRA/TSRA SHOULD SURGE INTO THE AREA WITH GUSTY SOUTH WINDS AND  
MVFR/IFR CIGS. THE LOWER CIGS AND TSRA THREAT SHOULD BE RATHER SHORT  
LIVED OVER A 3-4 HOUR WINDOW LATE MORNING THROUGH EARLY AFTERNOON  
BEFORE LIFTING OUT OF THE AERODROME SPACE. HOWEVER, VERY STRONG S/SW  
WINDS WILL FILL IN BEHIND THE SHRA WITH GUSTS 30KT OR HIGHER  
THROUGHOUT THE AFTERNOON.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
PERIODS OF SHRA WITH THE POTENTIAL FOR ISOLATED TSRA ALONG WITH  
ERRATIC WIND DIRECTIONS WILL BE THE MAIN WEATHER ISSUES AS THICK  
MIDLEVEL CIGS DEVELOP OVER THE AREA. WINDS SHOULD BECOME MORE  
VARIABLE IN DIRECTION OVERNIGHT, THEN OBTAINING AN E/SE COMPONENT  
SATURDAY. SCATTERED SHOWERS WOULD MOST LIKELY IMPACT KBLH BY EARLY  
AFTERNOON AS 10K FT CIGS COVER THE AREA. AT THIS POINT, A VCSH  
ADEQUATELY DESCRIBES THE COVERAGE, THOUGH ENOUGH ODDS FOR TSRA EXIST  
AT KBLH TO INCLUDE A PROB30. UNCERTAINTY IN WINDS AND WEATHER GROW  
SIGNIFICANTLY SATURDAY NIGHT AND SUNDAY AS A PERIOD OF HIGH IMPACT  
WEATHER MOVES INTO THE REGION.  
 
 
   
FIRE WEATHER  
 
A MUCH MORE UNSETTLED WEATHER PATTERN WILL DEVELOP OVER THE WEEKEND  
AS INCREASING MOISTURE ASSOCIATED WITH THE REMNANTS OF TROPICAL  
STORM RACHEL BRINGS INCREASING RAIN CHANCES. THE CHANCES FOR SHOWERS  
AND STORMS INCREASE STARTING SATURDAY AFTERNOON/EVENING AND  
CONTINUES INTO SUNDAY WITH A GREATER THAN 50-70% CHANCE OF WETTING  
RAINFALL AREA WIDE. WINDS WILL ALSO INCREASE SIGNIFICANTLY,  
ESPECIALLY LATE SATURDAY NIGHT THROUGH SUNDAY WITH WIDESPREAD GUSTS  
EXCEEDING 30-40 MPH. WITH THE INCREASING MOISTURE AND COOLER  
TEMPERATURES, MINRH VALUES WILL INCREASE FROM 25-40% SATURDAY TO 45-  
70% ON SUNDAY ALONG WITH GOOD TO EXCELLENT OVERNIGHT RECOVERIES.  
ANOTHER WEATHER SYSTEM WILL BRING ADDITIONAL CHANCES FOR WETTING  
RAINFALL EARLY NEXT WEEK, MAINLY FOR THE EASTERN DISTRICTS, BEFORE  
QUIETER WEATHER SETTLES IN BY THE MIDDLE OF THE WEEK.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...WIND ADVISORY FROM 2 AM TO 5 PM MST SUNDAY FOR AZZ530>533-535-  
536.  
 
WIND ADVISORY FROM 8 AM TO 5 PM MST SUNDAY FOR AZZ534-537>563.  
 
CA...WIND ADVISORY FROM 2 AM TO 5 PM PDT SUNDAY FOR CAZ560>570.  
 
 
 
 
 
SHORT TERM...WHITTOCK  
LONG TERM...LOJERO  
AVIATION...18  
FIRE WEATHER...WHITTOCK/LOJERO  
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