780  
FXUS65 KPSR 170953  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
253 AM MST FRI JUL 17 2026  
   
KEY MESSAGES  
 
- SHOWER ACTIVITY WILL GRADUALLY DIMINISH THIS MORNING WITH ONLY  
ISOLATED CHANCES MAINLY DURING THE AFTERNOON. TYPICAL MONSOON  
SHOWER AND THUNDERSTORM CHANCES WILL THEN FAVOR THE ARIZONA  
HIGH TERRAIN THIS WEEKEND.  
 
- BELOW NORMAL TEMPERATURES ARE EXPECTED ACROSS MUCH OF ARIZONA  
TODAY THROUGH EARLY NEXT WEEK WHILE SOUTHEAST CALIFORNIA  
MAINTAINS NEAR NORMAL READINGS.  
 
- THUNDERSTORM CHANCES SHOULD INCREASE DURING THE FIRST HALF OF  
NEXT WEEK WITH LOWER DESERT CHANCES BY TUESDAY.  
 
 
   
SHORT TERM /TODAY THROUGH SATURDAY/  
 
A WEAKENING MCS IS CURRENTLY SITTING OVER THE PHOENIX FOOTHILLS  
AND HIGHER TERRAIN NORTH OF PHOENIX. RAINFALL RATES HAVE  
DIMINISHED CONSIDERABLY SINCE LAST EVENING WITH MOST LOCATIONS  
STAYING UNDER 0.25" HOUR. A POCKET OF MODERATE RAIN SHOWERS WITH  
SOME EMBEDDED THUNDER REMAINS FARTHER TO THE NORTH BETWEEN PHOENIX  
AND FLAGSTAFF. DESPITE THE MODEST ASCENT STILL IN PLACE, THE  
ATMOSPHERE HAS BECOME LESS AND LESS UNSTABLE. HI-RES CAMS ARE IN  
FAIRLY GOOD AGREEMENT THIS MCS WILL CONTINUE TO DISSIPATE THROUGH  
SUNRISE WITH THE BEST CHANCE OF ANY ADDITIONAL DEVELOPMENT FROM  
WESTERN PORTIONS OF PHOENIX THROUGH THE REST OF WESTERN MARICOPA  
COUNTY. WE ARE EXPECTING TO ALLOW THE FLOOD WATCH TO EXPIRE AT 12Z  
EVEN THOUGH SOME ADDITIONAL SHOWERS ARE LIKELY DURING THE MORNING  
HOURS. GIVEN THE LOW INSTABILITY ENVIRONMENT AND THE EXTENSIVE  
CLOUDINESS THAT IS LIKELY TO LAST INTO THE AFTERNOON HOURS,  
ADDITIONAL DESTABILIZATION IS NOT LIKELY TO BE ENOUGH TO SPARK  
OFF MUCH IF ANY CONVECTION THIS AFTERNOON. DRIER AIR WILL ALSO  
START TO WORK INTO SOUTHWESTERN AND THEN CENTRAL ARIZONA LATER  
TODAY. TEMPERATURES WILL STRUGGLE TO WARM INTO THE 90S ACROSS THE  
SOUTH- CENTRAL ARIZONA LOWER DESERTS THIS AFTERNOON, WHILE HIGHS  
ACROSS SOUTHEAST CALIFORNIA AND PORTIONS OF WESTERN ARIZONA SHOULD  
TOP 100 DEGREES UNDER AT LEAST PARTLY SUNNY SKIES.  
 
GUIDANCE IS FINALLY IN GOOD AGREEMENT THE DRYING SHOULD EXTEND FAR  
ENOUGH THROUGH CENTRAL ARIZONA THAT SATURDAY WILL BE AN OVERALL  
QUIET WEATHER DAY FOR MUCH OF THE AREA. SOME ISOLATED TO POSSIBLY  
SCATTERED SHOWERS AND WEAK THUNDERSTORMS ARE EXPECTED OVER THE  
ARIZONA HIGH TERRAIN, BUT THE CHANCE OF ANY OF THIS ACTIVITY  
SURVIVING INTO THE LOWER DESERTS IS NO MORE THAN 10%. TEMPERATURES  
WILL BEGIN TO RECOVER ON SATURDAY WITH MID TO UPPER 90S IN THE  
PHOENIX AREA, BUT HIGHER THAN TYPICAL HUMIDITIES WILL STILL MAKE  
IT FEEL UNCOMFORTABLE.  
 
 
   
LONG TERM /SUNDAY THROUGH THURSDAY/  
 
THE EASTERLY WAVE CURRENTLY CENTERED OVER WEST TEXAS WILL UNDERGO  
SOME WEAKENING INTO THE WEEKEND, BUT GUIDANCE SHOWS IT FINALLY  
DRIFTING WEST SOUTHWESTWARD CLOSER TO OUR REGION BY SUNDAY. SUNDAY  
STILL LOOKS TO BE AN OVERALL QUIET DAY AS MOISTURE SHOULD STILL BE  
LIMITED, BUT WITH INCREASING HIGHER LEVEL ASCENT ANY CONVECTION  
THAT BUILDS OVER THE ARIZONA HIGH TERRAIN SHOULD BE MORE ROBUST.  
SOME GUIDANCE IS EVEN HINTING AT PUSHING SOME RAIN INTO THE LOWER  
DESERTS AT SOME POINT SUNDAY EVENING OR SUNDAY NIGHT, BUT THAT IS  
OF LOW CONFIDENCE AT THE MOMENT.  
 
BY MONDAY INTO TUESDAY, THE EASTERLY WAVE IS LIKELY TO BE MOVING  
INTO SOUTHEASTERN ARIZONA WITH MOIST EASTERLY FLOW SPREADING OVER  
THE REGION AGAIN ON MONDAY. WHETHER ENOUGH MOISTURE WILL ADVECT  
INTO THE AREA FOR LOWER DESERT CONVECTION TO OCCUR ON MONDAY IS  
STILL UNKNOWN, BUT IT SEEMS LIKELY AT LEAST ONE DAY DURING THE  
FIRST HALF OF NEXT WEEK WILL BE A FAIRLY ACTIVE MONSOON DAY. WE  
MAY EVEN HAVE TO WORRY ABOUT SEVERE WIND THREAT BY AROUND TUESDAY  
AS MID LEVEL WINDS ARE SHOWN TO INCREASE ENOUGH TO POSE A THREAT  
FOR LONGER LASTING STORMS AND/OR MCS DEVELOPING AND MAKING IT OFF  
THE HIGH TERRAIN. OF COURSE, THIS IS STILL QUITE UNCERTAIN AS IT  
WILL DEPEND ON THE STRENGTH AND THE PROGRESSION OF THE EASTERLY  
WAVE. GUIDANCE SHOWS THE DISTURBANCE EVENTUALLY MOVING TO OUR WEST  
BY NEXT THURSDAY AS THE SUBTROPICAL HIGH IS FAVORED TO BECOME  
MORE ESTABLISHED OVER NEW MEXICO OR TEXAS. DEPENDING ON HOW FAR  
SOUTH AND WEST THE HIGH SETS UP, WE MAY BE IN FOR ANOTHER DRIER  
AND HOT MONSOON PERIOD BY NEXT WEEKEND. CHANCES LOOK DECENT FOR  
AT LEAST A DOWNTREND IN RAIN CHANCES LATE NEXT WEEK OR BY NEXT  
WEEKEND AS GUIDANCE FAVORS THE GRADUAL DOWNTREND IN MOISTURE OVER  
THE REGION.  
 
TEMPERATURES ARE FORECAST TO GRADUALLY CREEP UPWARD NEXT WEEK,  
BUT LOCATIONS ACROSS SOUTH-CENTRAL AND EASTERN ARIZONA ARE  
EXPECTED TO STAY BELOW NORMAL FOR AT LEAST THE FIRST HALF OF THE  
WEEK. THE WESTERN LOWER DESERTS ARE LIKELY TO STAY IN THE NORMAL  
RANGE MUCH OF THE WEEK. IF THE RIDGE DOES EVENTUALLY SET UP JUST  
TO OUR EAST, WE MAY EVENTUALLY HAVE TO DEAL WITH HIGHS TOPPING 110  
DEGREES AGAIN BY NEXT WEEKEND.  
 
 
   
AVIATION  
UPDATED AT 0515Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
SHOWERS WITH EMBEDDED THUNDERSTORMS WILL CONTINUE ACROSS THE  
REGION THROUGH THE OVERNIGHT PERIOD, WITH COVERAGE GRADUALLY  
TAPERING OFF THROUGH FRIDAY MORNING WITH MAINLY DRY CONDITIONS  
EXPECTED BY THE AFTERNOON HOURS. THE OVERALL WINDS WILL GENERALLY  
BE OUT OF THE EAST THROUGHOUT MOST OF THE TAF PERIOD, WITH NO  
ANTICIPATION OF A WESTERLY WIND SHIFT OCCURRING FRIDAY AFTERNOON  
AT THIS TIME. SCT-BKN MID TO HIGH CLOUDS AOA 10 KFT WILL BE  
COMMON THROUGHOUT THE TAF PERIOD, ALTHOUGH SOME LOWER CLOUD BASES  
AS LOW AS 6-7 KFT WILL BE POSSIBLE TEMPORARILY IN ANY HEAVIER  
SHOWER/THUNDERSTORM ACTIVITY.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED DURING THE NEXT 24 HOURS  
UNDER PASSING MID TO HIGH CLOUD DECKS. WINDS WILL GENERALLY REMAIN  
OUT OF THE SOUTHEAST AT KIPL AND OUT OF THE SOUTH AT KBLH WITH  
OVERALL SPEEDS GENERALLY AOB 12 KTS.  
 
 
   
FIRE WEATHER  
 
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE OVER THE ARIZONA  
DISTRICTS INTO THIS AFTERNOON WITH MUCH LOWER CHANCES INTO  
WESTERN DISTRICTS. ACTIVITY OVER SOUTH-CENTRAL ARIZONA WILL STILL  
BE CAPABLE OF PRODUCING LOCALIZED FLOODING THROUGH EARLY AFTERNOON  
BEFORE DRYING BEGINS TO MOVE IN FROM THE SOUTH. ELEVATED SOUTHERLY  
WINDS ARE ANTICIPATED MUCH OF THE PERIOD FOR THE WESTERN  
DISTRICTS WITH LIGHT WINDS ELSEWHERE. ELEVATED HUMIDITIES TODAY  
WILL KEEP MINIMUM AFTERNOON HUMIDITY LEVELS FROM 30% IN WESTERN  
DISTRICTS TO 40-50% OVER THE EASTERN DISTRICTS. A GRADUAL DRYING  
TREND OVER THE WEEKEND WILL DROP MINRHS TO 20-35% WITH ANY WETTING  
RAIN CHANCES FAVORING THE ARIZONA HIGH TERRAIN.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...FLOOD WATCH UNTIL 5 AM MST EARLY THIS MORNING FOR AZZ534-537>563.  
 
CA...NONE.  
 
 
 
 
SHORT TERM...KUHLMAN  
LONG TERM...KUHLMAN  
AVIATION...LOJERO  
FIRE WEATHER...KUHLMAN  
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