076  
FXUS65 KPSR 140520  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1020 PM MST MON JUL 13 2026  
   
UPDATE  
06Z AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- A FAIRLY TYPICAL MONSOON PATTERN WILL CONTINUE THROUGH THE  
FIRST HALF OF THE WEEK, WITH EARLY AFTERNOON SHOWERS AND  
THUNDERSTORMS FORMING OVER THE ARIZONA HIGH TERRAIN DAILY  
FOLLOWED BY CHANCES OVER THE LOWER DESERTS FOCUSED LATER IN THE  
AFTERNOON INTO THE EVENING.  
 
- A DISTURBANCE MAY APPROACH THE REGION FROM THE EAST DURING THE  
LATTER HALF OF THE WEEK, BRINGING FAVORABLE CONDITIONS FOR MORE  
WIDESPREAD SHOWERS AND THUNDERSTORMS.  
 
- SEASONABLY HOT TEMPERATURES WILL PERSIST THROUGH THE MIDDLE OF  
THE WEEK RESULTING IN WIDESPREAD MODERATE HEAT RISK AND LOCALLY  
MAJOR HEAT RISK ON WEDNESDAY IN SOUTHEAST CALIFORNIA, FOLLOWED  
BY COOLER TEMPERATURES LATE WEEK.  
 
 
   
SHORT TERM /TODAY THROUGH TUESDAY/  
 
AS OF 1:13 AM MST THIS MORNING PHOENIX SKY HARBOR WAS ABLE TO  
MEASURE WITH A TOTAL OF 0.01", THE FIRST MEASURABLE RAINFALL SINCE  
MARCH 29TH, 2026. MANY SURROUNDING AREAS IN THE PHOENIX METRO WERE  
ALSO ABLE TO MEASURE BETWEEN 0.01"-0.05" WHILE AREAS IN SOUTHERN  
MARICOPA COUNTY, PINAL COUNTY AND THE HIGHER TERRAINS RECEIVED  
MEASUREMENTS BETWEEN 0.25"-0.75" TO LOCALLY HIGHER AMOUNTS. THIS WAS  
DUE TO A CLUSTER OF SEVERE THUNDERSTORMS THAT DEVELOPED IN SOUTHERN  
MARICOPA COUNTY AND PINAL COUNTY YESTERDAY EVENING. WHILE  
MEASURABLE RAINFALL IS ALWAYS EXCITING, ESPECIALLY HERE IN THE  
LOWER DESERTS, THAT WAS NOT THE HIGHLIGHT OF YESTERDAYS ACTIVITY AS  
THOSE AREAS, AND EVEN INTO THE WEST VALLEY, RECEIVED THEIR FIRST  
DUST STORM WARNING SINCE SEPTEMBER 26TH, 2025. THE STORMS THAT  
DEVELOPED WERE ABLE TO PRODUCE SOUTHEASTERLY GUSTS UP TO 45-50 MPH  
AT TIMES, PICKING UP A LARGE AMOUNT OF DUST AND REDUCING VISIBILITIES  
TO UNDER 1/4 OF A MILE TO NEAR ZERO IN SOME AREAS LAST NIGHT.  
 
TODAY GOES MID-LEVEL WV IMAGERY SHOWS THE HIGH PRESSURE OVER THE  
NORTHERN PLAINS ASSOCIATED WITH A LARGE AREA OF DRY AIR. THE  
POSITION OF THIS HIGH PRESSURE IS WHAT HAS SHIFTED FLOW ALOFT OVER  
THE DESERT SW OUT OF THE SOUTHEAST, AND ALLOWING FOR GOOD MOISTURE  
ADVECTION. THIS INCREASE IN MOISTURE HAS LEAD TO PWATS BETWEEN 1.5"-  
1.8" ACROSS A VAST MAJORITY OF THE CWA WITH LOCALLY HIGHER, CLOSER  
TO 2", NEAR THE GULF OF CALIFORNIA. THIS MOISTURE IS EXPECTED TO  
LINGER THROUGHOUT THE WEEK WITH 1000MB-700MB MIXING RATIOS STAYING  
GENERALLY BETWEEN 10-12 G/KG ACROSS THE REGION. WITH YESTERDAY'S  
ACTIVITY THE ATMOSPHERE IS SLIGHTLY WORKED OVER RESULTING IN  
CHANCES TODAY FOR ACTIVITY TO BE LOWER, HOWEVER NOT ZERO, WITH  
POPS BETWEEN 15-25% IN THE METRO, AND BETWEEN 30-50% IN THE  
FOOTHILLS. THE LATEST HRRR RUN DOES SHOW ANOTHER ROUND OF STORMS  
DEVELOPING TODAY IN MUCH OF THE SAME AREAS AS YESTERDAY (EASTERN  
HIGH TERRAIN AND SOUTH CENTRAL AZ), HOWEVER WINDS ARE EXPECTED TO  
BE LOWER THIS AFTERNOON WITH THE HREF GUIDANCE SHOWING ONLY A  
50-70% CHANCE (COMPARED TO SUNDAY'S 70-90%) OF WINDS ABOVE 35 MPH  
FOCUSED ALONG A CORRIDOR FROM PHOENIX SOUTH/SOUTHEASTWARD, AND NOT  
NEAR AS WIDESPREAD COMPARATIVELY. ADDITIONALLY WITH YESTERDAYS  
RAINFALL DUST MAY NOT BE AS EASILY LOFTED, HINDERING CHANCES FOR  
WIDESPREAD BLOWING DUST TONIGHT. ANY ACTIVITY THAT DOES FORM IN  
OUR REGION TONIGHT WILL CONTINUE TO BE HIGHLY CONDITIONAL ON  
UPSTREAM ACTIVITY AND IF OUTFLOWS FROM CENTRAL AZ HIGH TERRAIN  
STORMS CAN TRIGGER ADDITIONAL CELLS. BY TUESDAY, THERMODYNAMICS  
MAY BE SLIGHTLY MORE FAVORABLE FOR STRONG STORMS, HOWEVER, FLOW  
ALOFT WEAKENS FURTHER AND DIRECTIONS BECOME COMPLEX AS WEAK  
ANTICYCLONIC AND CYCLONIC CIRCULATIONS BEGIN TO IMPINGE ON THE  
REGION, CREATING A DEFORMATION AREA. THE THREAT FOR LOWER DESERT  
STORMS WILL BE EVEN MORE CONDITIONAL ON LIFTING MECHANISMS FROM  
EARLIER STORMS OR SUBTLE LIFT FROM THE DEFORMATION ZONES DRAPED  
ACROSS THE REGION.  
 
OTHERWISE, TEMPERATURES THIS AFTERNOON WILL BE IN THE LOW TO MID  
100S ACROSS THE LOWER DESERTS, WITH THE PHOENIX METRO SLIGHT HIGHER  
BETWEEN 105F-107F. TUESDAY'S AFTERNOON HIGHS WILL BE SLIGHTLY  
WARMER, WITH TEMPERATURES RANGING BETWEEN 105F-111F. DESPITE THE  
STORY WEATHER THESE TEMPERATURES ARE STILL A FEW DEGREES ABOVE NORMAL  
KEEPING WIDESPREAD MODERATE HEATRISK IN PLACE. WITH THAT SAID, BE  
SURE TO KEEP HEAT SAFETY IN MIND IF SPENDING TIME OUTDOORS.  
 
 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/  
 
THERE IS STILL EXCELLENT AGREEMENT WITHIN THE EPS AND GEFS  
MEMBERS REGARDING THE PLACEMENT OF THE UPPER HIGH OVER THE  
NORTHERN PLAINS AND UPPER MIDWEST THROUGH MIDWEEK BEFORE  
RETROGRADING OVER THE CENTRAL ROCKIES BY THE LATTER HALF OF THE  
WEEK. THE OVERALL POSITION OF THE 500 MB HIGH WILL MAINTAIN DEEP  
EASTERLY FLOW ACROSS THE DESERT SOUTHWEST, HELPING ENHANCE  
MOISTURE TRANSPORT. LATEST EPS AND GEFS CONTINUE TO SHOW PWATS  
HOVERING AROUND 1.5"-1.8" THROUGH THE ENTIRE WEEK WITH LOW-LEVEL  
MIXING RATIOS REMAINING BETWEEN 10-12 G/KG. THEREFORE, CONDITIONS  
WILL CONTINUE TO REMAIN CONDUCIVE FOR DAILY THUNDERSTORM ACTIVITY  
WITH VARIATIONS IN THE OVERALL COVERAGE. BOTH THE MEAN OF THE EPS  
AND GEFS SHOW AN UPTICK IN QPF ACROSS THE REGION BY THE END OF  
THIS WEEK DUE TO AN EASTERLY WAVE/INVERTED TROUGH APPROACHING THE  
AREA BY THURSDAY-FRIDAY. IF THIS OCCURS, THIS TROUGHING FEATURE  
WILL LIKELY ENHANCE CONVECTIVE ACTIVITY POTENTIALLY INTRODUCE A  
RISK FOR HEAVY RAINFALL ACROSS PORTIONS OF AZ. THIS WILL HAVE TO  
BE MONITORED CLOSELY IN THE COMING DAYS.  
 
TEMPERATURES ARE EXPECTED TO PEAK WEDNESDAY MOSTLY BETWEEN  
105F-110F ACROSS THE ARIZONA LOWER DESERTS, BUT SOME AREAS OF  
MAJOR HEATRISK ENTER THE PICTURE FOR PORTIONS OF SOUTHEAST CA AND  
ALONG THE LOWER COLORADO RIVER VALLEY, WHERE LATEST NBM FORECAST  
SHOWS HIGHS AS HIGH AS 113F AND LOWS IN THE MIDDLE TO UPPER 80S  
THANKS TO THE INEFFICIENT OVERNIGHT RADIATIVE COOLING FROM HIGHER  
HUMIDITY AND LIKELY SOME MID-HIGH CLOUD COVER. THE NBM CONTINUES  
TO INDICATE TEMPERATURES COOLING TO WELL BELOW NORMAL BY THE END  
OF THE WEEK WITH HIGHS FALLING INTO THE 90S TO AROUND 100 DEGREES  
ACROSS THE LOWER DESERTS BY FRIDAY. THIS IS LIKELY DUE TO THE  
INCREASED SIGNAL FOR THICKER CLOUD COVER AND THE POTENTIAL FOR  
MORE WIDESPREAD RAINFALL.  
 
 
   
AVIATION  
UPDATED AT 0515Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
AFTER WIDESPREAD STRONG GUSTY WINDS AND THUNDERSTORM ACTIVITY  
EARLIER THIS EVENING, CONDITIONS ARE IMPROVING ACROSS THE AREA.  
CONDITIONS THROUGH TUESDAY AFTERNOON SHOULD REMAIN TRANQUIL WITH  
THE OVERALL WIND PATTERN FOLLOWING THE TYPICAL DIURNAL TENDENCIES  
WITH EASTERLY WINDS OVERNIGHT THROUGH EARLY TUESDAY MORNING  
SHIFTING OUT OF THE WEST LATE TUESDAY MORNING/EARLY AFTERNOON WITH  
SOME OCCASIONAL AFTERNOON GUSTS IN THE MID TO UPPER TEENS. AT THIS  
TIME, THERE IS A MUCH LOWER CHANCE OF THUNDERSTORM ACTIVITY  
TUESDAY EVENING WITH A BETTER POTENTIAL OF AN EASTERLY OUTFLOW  
FROM DISTANT ACTIVITY. OUTFLOW MAGNITUDE WILL BE ALL DEPENDENT ON  
THE OVERALL COVERAGE AND INTENSITY OF DISTANT STORM ACTIVITY. SCT  
TO OCCASIONAL BKN MID TO HIGH CLOUDS WILL PREVAIL THROUGH THE  
OVERNIGHT HOURS BEFORE COVERAGE DECREASES TO FEW BY TUESDAY  
MORNING.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED THROUGHOUT THE TAF PERIOD  
UNDER FEW TO SCT MID TO HIGH CLOUDS. AT KIPL, LIGHT AND VARIABLE  
WINDS CURRENTLY WILL SHIFT OUT OF THE SOUTHEAST BY EARLY TUESDAY  
MORNING AND REMAIN OUT OF THE SOUTHEAST THROUGH THE AFTERNOON  
HOURS WITH ANOTHER TEMPORARY SHIFT OUT OF THE WEST DURING THE  
EARLY EVENING HOURS. AT KBLH, WINDS WILL GENERALLY FLUCTUATE  
BETWEEN THE SOUTH-SOUTHEAST TO SOUTHWEST WITH A PERIOD OF LIGHT  
VARIABILITY TUESDAY MORNING. OVERALL WIND SPEEDS ARE EXPECTED TO  
REMAIN AOB 10 KTS.  
 
 
   
FIRE WEATHER  
 
SEASONABLY HOT TEMPERATURES WILL PREVAIL THROUGH THE NEXT SEVERAL  
DAYS AS READINGS WILL BE NEAR TO SLIGHTLY ABOVE NORMAL. DAILY  
THUNDERSTORM ACTIVITY WILL BE POSSIBLE THROUGH THIS WEEK WITH THE  
POTENTIAL FOR MORE WIDESPREAD WETTING RAINFALL INCREASING ACROSS  
THE EASTERN DISTRICTS THROUGHOUT THIS WEEK, WITH HIGHER CHANCES BY  
THURSDAY AND FRIDAY. DUE TO INCREASING BOUNDARY LAYER MOISTURE,  
AFTERNOON HUMIDITY LEVELS WILL REMAIN IN A 20-30% RANGE WHICH WILL  
KEEP ANY FIRE WEATHER CONCERNS AT A MINIMUM. OVERNIGHT RECOVERIES  
WILL BE FAIR TO GOOD, OR BETWEEN 40-70%. OUTSIDE OF ANY  
THUNDERSTORM DRIVEN OUTFLOW, WINDS SHOULD FAVOR DIURNAL TRENDS  
WITH THE TYPICAL AFTERNOON BREEZINESS AROUND 20-25 MPH.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
SHORT TERM...RYAN/WHITTOCK  
LONG TERM...SALERNO/WHITTOCK  
AVIATION...LOJERO  
FIRE WEATHER...RYAN/WHITTOCK  
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