230  
FXUS65 KPSR 111836  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1136 AM MST TUE AUG 11 2026  
   
UPDATE  
UPDATED AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- BETTER MOISTURE AND MORE FAVORABLE CONDITIONS FOR MONSOON STORM  
DEVELOPMENT IS EXPECTED THROUGH MIDWEEK WITH THE MOST WIDESPREAD  
ACTIVITY ACROSS SOUTH-CENTRAL AND EASTERN ARIZONA.  
 
- LOCALLY HEAVY RAINFALL AND GUSTY THUNDERSTORM WINDS WILL REMAIN  
POSSIBLE THROUGH THURSDAY BEFORE DRYING CONDITIONS ENDS RAIN  
CHANCES AS EARLY AS FRIDAY.  
 
- COOLING TEMPERATURES ARE EXPECTED THROUGH MIDWEEK, BRIEFLY  
FALLING TO BELOW NORMAL WEDNESDAY THROUGH FRIDAY.  
 
 
   
SHORT TERM /TODAY THROUGH THURSDAY/  
 
SCATTERED SHOWERS AND ELEVATED THUNDERSTORMS WILL CONTINUE TO BE  
POSSIBLE THROUGH AROUND SUNRISE WITH THE MAIN AREA OF FOCUS ACROSS  
MARICOPA COUNTY. DESPITE FAIRLY STRONG CIN IN THE LOWER LEVELS,  
THE ONGOING ACTIVITY FROM THE EVENING HOURS HAS ALLOWED FOR THE  
ELEVATED CAPE OF OVER 1000 J/KG TO BE TAPPED INTO ACROSS THE AREA.  
THE MAIN CONCERN OVER THE NEXT FEW HOURS WILL BE LIGHTNING AND  
VERY LOCALIZED HEAVY RAINFALL. A FEW SPOTS COULD RECEIVE UP TO  
AROUND 1 INCH OF RAIN, BUT MOST LOCATIONS WILL STAY UNDER 0.25"  
THROUGH THE REST OF THE NIGHT.  
 
LOOKING AT THE LARGER PICTURE, THE SUBTROPICAL HIGH CENTERED OVER  
NORTHWEST NEW MEXICO WILL GRADUALLY SHIFT TO THE EAST AS A WEAK  
PACIFIC TROUGH ATTEMPTS TO MOVE IN FROM THE WEST STARTING  
WEDNESDAY. FOR THE REST OF TODAY, A MOSTLY OVERTURNED ATMOSPHERE  
IS LIKELY TO LIMIT SHOWER AND THUNDERSTORM ACTIVITY COMPARED TO  
THE LAST COUPLE OF DAYS. HI-RES CAMS SHOW STORMS FIRING OVER THE  
EASTERN AZ HIGH TERRAIN THIS AFTERNOON WITH A WEAK SOUTHEASTERLY  
STEERING FLOW POTENTIALLY DIRECTING SOME OF THE ACTIVITY INTO THE  
SOUTH-CENTRAL AZ LOWER DESERTS THIS EVENING. DESPITE AMPLE  
ELEVATED INSTABILITY, STRONG CIN IS LIKELY TO BE DIFFICULT TO  
OVERCOME OVER THE LOWER DESERTS RESULTING IN POPS OF 10-20%.  
CHANCES WILL PERSIST INTO EARLY WEDNESDAY MORNING, BUT THE  
ACTIVITY IS EXPECTED TO BE MUCH MORE SPARSE THAN WHAT WE ARE  
RECEIVING AT THE MOMENT.  
 
UNCERTAINTY CLIMBS ON WEDNESDAY AS THE WEAK TROUGH BEGINS TO ENTER  
WESTERN PORTIONS OF THE REGION TURNING THE FLOW OUT OF THE SOUTH  
SOUTHWEST. THE INCOMING TROUGH IS EXPECTED TO INCREASE UPPER LEVEL  
FORCING ACROSS MUCH OF THE AREA FOR WEDNESDAY INTO EARLY THURSDAY,  
BUT AS THE FLOW SHIFTS OUT OF THE SOUTH SOUTHWEST SOME DRY AIR  
WILL BEGIN TO FILTER INTO WESTERN AND THEN SOUTH-CENTRAL ARIZONA.  
HOWEVER, PLENTY OF MOISTURE WILL REMAIN FROM AROUND PHOENIX AND  
AREAS TO THE EAST AND NORTHEAST OF PHOENIX. THE BIGGEST QUESTION  
WILL BE THE AREAS OF FOCUS FOR SHOWER AND STORMS FROM WEDNESDAY  
AFTERNOON THROUGH THURSDAY MORNING. GUIDANCE INDICATES THE BEST  
CHANCES FROM NORTHERN AND EASTERN PORTIONS OF PHOENIX INTO THE  
HIGHER TERRAIN WITH POPS OF 50-70% WITH DECREASING CHANCES TO THE  
SOUTH AND WEST. THE SOUTHWESTERLY STEERING FLOW WILL DIRECT ANY  
ACTIVITY TOWARD THE HIGH TERRAIN WITH SOME STORMS POTENTIALLY  
BECOMING ANCHORED TO A TERRAIN FEATURE AND/OR SOME POTENTIAL FOR  
TRAINING STORMS. A FASTER THAN NORMAL STORM MOVEMENT SHOULD HELP  
TO LIMIT THE HEAVY RAINFALL THREAT, BUT THE AFOREMENTIONED  
FACTORS COULD STILL LEAD TO SOME INSTANCES OF FLASH FLOODING. THE  
ACTIVITY IS LIKELY TO PERSIST DURING THE OVERNIGHT HOURS/THURSDAY  
MORNING, BUT THE THREAT FOR HEAVY RAINFALL IS LIKELY TO GRADUALLY  
DECREASE.  
 
THE INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY AND CLOUDS OVER  
THE NEXT COUPLE OF DAYS WILL HELP TO BRING SOME RELIEF FROM THE  
RECENT HEAT. FORECAST HIGHS TODAY DROP BACK TO AROUND NORMAL AND  
THEN TO BELOW NORMAL FOR MUCH OF ARIZONA STARTING WEDNESDAY.  
FORECAST HIGHS SEVERAL DEGREES BELOW NORMAL ARE EXPECTED FOR  
THURSDAY AND FRIDAY.  
 
 
   
LONG TERM /FRIDAY THROUGH MONDAY/  
 
DRYING IS EXPECTED TO PICK UP ACROSS THE AREA DURING THE LATTER  
HALF OF THURSDAY WITH MOST OF THE SHOWER AND THUNDERSTORM  
POTENTIAL SHIFTING TO OVER THE ARIZONA HIGH TERRAIN. BY FRIDAY,  
ENOUGH DRY AIR IS EXPECTED TO FILTER INTO THE AREA TO COMPLETELY  
END RAIN CHANCES ACROSS THE LOWER DESERTS WHILE LIMITED CHANCES  
ARE FORECAST FOR THE HIGH TERRAIN. THE SUBTROPICAL HIGH IS  
EXPECTED TO STAY CENTERED ACROSS THE SOUTHEASTERN U.S. THROUGH AT  
LEAST THE WEEKEND WITH BROAD TROUGHING OVER MUCH OF THE WESTERN  
U.S. THIS WILL KEEP DRY AIR IN PLACE THROUGH AT LEAST THE UPCOMING  
WEEKEND WITH AT MOST SLIGHT CHANCES FOR AFTERNOON CONVECTION OVER  
THE FAR EASTERN ARIZONA HIGH TERRAIN. ENSEMBLES DO SHOW THE  
SUBTROPICAL HIGH BECOMING MORE ELONGATED LATE THIS WEEKEND WITH  
HEIGHTS GRADUALLY INCREASING OVER OUR REGION. AS A RESULT,  
TEMPERATURES ARE LIKELY TO CLIMB BACK TO AROUND OR EVEN A FEW  
DEGREES ABOVE NORMAL BY SUNDAY OR MONDAY. THE NEXT POTENTIAL FOR  
RAIN COULD COME AS EARLY AS NEXT MONDAY OR TUESDAY, BUT  
UNCERTAINTY IS QUITE HIGH AT A WEEK AWAY.  
 
 
   
AVIATION  
UPDATED AT 1835Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
WEST WINDS WILL CONTINUE INTO THE OVERNIGHT HOURS. GUSTS INTO THE  
UPPER TEENS TO AROUND 20 KT IS EXPECTED DURING THE AFTERNOON AND  
EARLY EVENING HOURS. A DISTANT OUTFLOW FROM THE NE MAY AFFECT THE  
PHOENIX AIRSPACE DURING THE EVENING (02-05Z TIMEFRAME), BUT  
CONFIDENCE IS TOO LOW FOR TAF INCLUSION AT THIS TIME. THEN, A  
SECOND DISTANT OUTFLOW MAY REACH THE TERMINALS LATE EVENING INTO  
THE OVERNIGHT HOURS OUT OF THE SE, CONFIDENCE FOR THIS OUTFLOW IS  
ALSO TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. ANOTHER PERIOD OF  
VCSH/VCTS WILL NEED TO BE EVALUATED FOR THE OVERNIGHT PERIOD INTO  
WEDNESDAY MORNING, WITH 20-30% CHANCES FOR SPOTTY COVERAGE OF  
SHRA/TS ACROSS THE PHOENIX AIRSPACE. WINDS TOMORROW MORNING ARE  
EXPECTED TO BE SIMILAR TO THIS MORNING AT KPHX WITH AN EARLIER  
SHIFT TO WESTERLY AROUND 15Z AT KPHX AND KIWA.LOWEST CLOUD BASES  
WILL MOSTLY STAY AT OR ABOVE 10K FT AGL THROUGH THE PERIOD.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
THE POTENTIAL FOR STRONG OUTFLOW WINDS TO ONCE AGAIN REACH THE  
TERMINALS AND VCSH/VCTS CONDITIONS THIS AFTERNOON WILL BE THE  
PRIMARY AVIATION WEATHER CONCERNS. WINDS WILL FAVOR A SOUTHERLY  
DIRECTION AT KBLH WITH AFTERNOON GUSTS TO AROUND 20 KTS. VCSH/VCTS  
MAY DEVELOP AT KBLH TUESDAY AFTERNOON BEGINNING AROUND 22Z. AT  
KIPL, WINDS WILL PRIMARILY FAVOR S-SE THROUGH THE TAF PERIOD, WITH  
A PERIOD OF W-SW LATER TUESDAY AFTERNOON AND EVENING ASSOCIATED  
WITH STORM OUTFLOW AND VCSH/VCTS. VCSH/VCTS MAY DEVELOP AT KIPL  
TUESDAY AFTERNOON BEGINNING AROUND 00Z. STRONG GUSTY AND ERRATIC  
WINDS ARE ALSO POSSIBLE WITH ANY OUTFLOWS. FEW TO SCT CLOUDS WILL  
BE COMMON OVER THE AREA WITH LOWEST BASES DOWN TO AROUND 10K FT  
AGL.  
 
 
   
FIRE WEATHER  
 
SCATTERED SHOWERS AND THUNDERSTORMS ARE ANTICIPATED EACH DAY  
THROUGH MIDWEEK ACROSS THE HIGHER TERRAIN AREAS OF THE EASTERN  
DISTRICTS, WITH SLIGHTLY LOWER CHANCES IN THE LOWER ELEVATIONS.  
THE BEST CHANCES WILL FALL DURING THE LATTER HALF OF WEDNESDAY.  
AFTERNOON MINRHS WILL RANGE BETWEEN 25-40% THROUGH WEDNESDAY WITH  
GOOD TO EXCELLENT OVERNIGHT RECOVERIES. ASIDE FROM GUSTY AND  
ERRATIC WINDS NEAR THUNDERSTORMS, THE OVERALL WIND PATTERN WILL  
FOLLOW THE DIURNAL TRENDS WITH MODEST AFTERNOON UPSLOPE GUSTS.  
NEAR TO BELOW NORMAL TEMPERATURES ARE EXPECTED THROUGH THE REST OF  
THE WEEK WITH DRYING CONDITIONS BY FRIDAY AND LASTING THROUGH NEXT  
WEEKEND.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
SHORT TERM...KUHLMAN  
LONG TERM...KUHLMAN  
AVIATION...WHITTOCK/BENEDICT  
FIRE WEATHER...KUHLMAN  
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