697  
FXUS65 KPSR 172347  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
447 PM MST FRI JUL 17 2026  
   
UPDATE...UPDATED 00Z AVIATION DISCUSSION
 
 

 
   
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/
 
 
OVERNIGHT AND EARLY MORNING SHOWERS AND THUNDERSTORMS BROUGHT  
WIDESPREAD RAINFALL ACROSS SC AZ WITH MOST OF THE ACCUMULATIONS  
IN THE EAST VALLEY, THE FOOTHILLS AND HIGHER TERRAINS. GOING FROM  
LOW TO HIGH THE WESTERN PORTIONS OF MARICOPA COUNTY RECEIVED ONLY  
AN AVERAGE BETWEEN 0.05"-0.35", MEANWHILE IN EASTERN MARICOPA  
COUNTY AND PINAL COUNTY 24HR ACCUMULATIONS WERE GENERALLY BETWEEN  
0.5"-1.25" WITH LOCALIZED AREAS RECEIVING BETWEEN 2"-2.5" IN THE  
HIGHER TERRAIN AREAS. THE LATER MORNING HOURS RECEIVED A FEW MORE  
LINGERING STORMS OVER HIGHER TERRAIN, WHERE MORE RAINFALL OCCURRED  
BUT AS OF THIS DISCUSSION HAVE NOT BEEN TAKEN INTO ACCOUNT FOR  
THE PREVIOUSLY MENTIONED TOTALS. HI-RES CAMS ARE IN GOOD AGREEMENT  
THAT THE SYSTEMS THAT DEVELOPED THROUGH THE LATE MORNING HOURS  
WILL PROGRESSIVELY DETERIORATE THROUGHOUT THE AFTERNOON HOURS.  
WHILE PWATS WILL REMAIN BETWEEN 1.5"-2" ACROSS THE REGION MOST OF  
THE ENERGY HAS BEEN LOST WITH MUCAPE FALLING TO BETWEEN 500-750  
J/KG THIS AFTERNOON, WITH CLOUD COVERAGE HINDERING CONVECTIVE  
POTENTIAL FOR FURTHER STORM DEVELOPMENT TODAY, ALTHOUGH NOT  
IMPOSSIBLE, ESPECIALLY IN THE HIGHER TERRAIN DUE TO THE NATURAL  
OROGRAPHIC LIFT. HOWEVER, THIS HAS LEAD TO POPS LATER THIS  
MORNING/EARLY AFTERNOON IN SC AZ TO BE MUCH LOWER THAN YESTERDAY'S  
FORECAST PACKAGE, DROPPING FROM 30-40% TO NOW NEAR 10-25%. AS FAR  
AS TEMPERATURES GO FOR THIS AFTERNOON, HIGHS ARE EXPECTED TO BE  
IN THE LOW TO MID 90S ACROSS SC AZ, WHILE THE WESTERN LOWER  
DESERTS, WILL BE IN THE LOW TO MID 100S.  
 
BY SATURDAY, BROAD UPPER LEVEL RIDGING WILL BE OVER THE DESERT SW  
WITH THE CORE OF THE HIGH PRESSURE EXPECTED TO BE OVER UT AND NM.  
WITH LESS STORM ACTIVITY, AND BROAD RIDGING, SKIES WILL BEGIN TO  
CLEAR IN THE AFTERNOON CAUSING TEMPERATURES TO CLIMB BACK INTO THE  
UPPER 90S TO NEAR 100 IN SC AZ AND REMAIN IN THE MID 100S IN THE  
WESTERN LOWER DESERTS. AS FAR AS SHOWER/THUNDERSTORM ACTIVITY  
SATURDAY, SOME ISOLATED TO POSSIBLY SCATTERED SHOWERS AND WEAK  
THUNDERSTORMS ARE POSSIBLE OVER THE ARIZONA HIGH TERRAIN, BUT THE  
CHANCE OF ANY OF THIS ACTIVITY SURVIVING INTO THE LOWER DESERTS IS  
NO MORE THAN 10%.  
 

 
   
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 2345Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
SHRA ACTIVITY AND POTENTIALLY SOME EMBEDDED TS SATURDAY MORNING  
WILL BE THE MAIN AVIATION WEATHER ISSUES THROUGHOUT THE TAF  
PERIOD. IN THE MEANTIME, TRANQUIL WEATHER SHOULD PREVAIL THROUGH  
THE EVENING HOURS AND AT LEAST INTO THE FIRST PART OF THE  
OVERNIGHT HOURS WITH WINDS GENERALLY LIGHT AND VARIABLE TO LIGHT  
EASTERLY. HEADING INTO THE EARLY MORNING HOURS ON SATURDAY, THE  
LATEST HI-RES GUIDANCE IS SHOWING AN AREA OF SHOWERS AND EMBEDDED  
TS DEVELOPING ACROSS PORTIONS NORTHERN AND NORTHEASTERN MARICOPA  
COUNTY, HOWEVER, TO WHAT EXTENT AND HOW CLOSE ACTIVITY WILL REACH  
THE TERMINAL SITES IS HIGHLY UNCERTAIN AT THIS TIME. THEREFORE,  
ONLY VCSH HAVE BEEN INTRODUCED FOR THE TERMINAL SITES FOR THIS TAF  
PACKAGE. EITHER WAY, CONDITIONS WILL IMPROVE BY THE EARLY  
AFTERNOON HOURS AS THE ACTIVITY TAPERS OFF. SIMILAR TO TODAY,  
UNCERTAINTY EXISTS WHETHER OR NOT THE TRADITIONAL AFTERNOON  
WESTERLY SHIFT WILL MATERIALIZE ON SATURDAY WITH WINDS POTENTIALLY  
ONCE AGAIN BEING LIGHT AND VARIABLE TO REMAINING OUT OF THE EAST.  
SCT-BKN CLOUDS AOA 10 KFT WILL BE COMMON THROUGHOUT THE TAF  
PERIOD.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION WEATHER CONCERNS ARE EXPECTED THROUGHOUT THE TAF  
PERIOD. OVERALL WIND PATTERN WILL REMAIN OUT OF THE SOUTHEAST AT  
KIPL AND FLUCTUATE BETWEEN THE SOUTH TO SOUTHEAST AT KBLH. THERE  
IS A POTENTIAL THIS EVENING OF AN OUTFLOW FROM TS ACTIVITY TO THE  
NORTHEAST POTENTIALLY AFFECTING KBLH AND TEMPORARILY SHIFTING THE  
WINDS OUT OF THE NORTHEAST. OVERALL WINDS SHOULD REMAIN UNDER 15  
KTS WITH THE POTENTIAL FOR PERIODS OF LIGHT VARIABILITY EARLY  
SATURDAY MORNING. FEW-SCT CLOUDS AOA 10 KFT WILL BE COMMON  
THROUGHOUT THE TAF PERIOD.  
 

 
   
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...NONE.  
CA...NONE.  

 
 

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