030  
FXUS65 KPSR 171954  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1254 PM 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/  
 
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 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 1730Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
VERY LOW CONFIDENCE FORECAST THROUGH SATURDAY MORNING WITH SHRA,  
LOWERING CIGS, AND VARYING WIND DIRECTIONS IMPACTING OPERATIONS.  
SCATTERED SHRA WILL BE COMMON THROUGH MID AFTERNOON WITH ACTIVITY  
CLEARING NORTHWEST TO SOUTHEAST. MVFR VSBY AND CIGS MAY BRIEFLY  
AFFECT TERMINALS WITH ANY SHRA DIRECTLY MOVING OVER THE AIRFIELD.  
WHILE EAST WINDS WILL BE PREFERRED INITIALLY, DIRECTIONS MAY BECOME  
HIGHLY VARIABLE THROUGH THE AFTERNOON WITH THE MOST CONVINCING  
GUIDANCE INDICATING A SWITCH TO NORTHERLY LATE AFTERNOON/EARLY  
EVENING. TIMING OF ANY DIRECTIONAL CHANGE AND EXACT HEADING CARRY  
VERY LOW CONFIDENCE.  
 
ADDITIONAL SHRA AND ASSOCIATED IMPACTS MAY BE POSSIBLE LATE TONIGHT  
INTO SATURDAY MORNING, HOWEVER GUIDANCE IS NOT OVERWHELMINGLY  
CONFIDENCE IN THIS OUTCOME. THUS, HAVE NOT INTRODUCED ANY VCSH/SHRA  
YET, HOWEVER MAY BE NEEDED IN FUTURE TAF UPDATES.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO WEATHER ISSUES WILL EXIST THROUGH SATURDAY AFTERNOON UNDER  
FREQUENT MID/HIGH CLOUD DECKS. CONFIDENCE IN WINDS IS ONLY MODERATE  
WITH A SE COMPONENT PREFERRED AT KIPL AND SOUTH AT KBLH. KIPL  
DIRECTIONS MAY TURN SW AS EARLY AS LATE AFTERNOON IN RESPONSE TO  
TSRA OVER BAJA, MEXICO. DIRECTIONAL VARIABILITY MAY BECOME COMMON BY  
SATURDAY MORNING.  
 
 
   
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...18  
FIRE WEATHER...KUHLMAN  
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