054  
FXUS65 KPSR 041126  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
426 AM MST MON MAY 4 2026  
   
UPDATE
 
12Z AVIATION DISCUSSION.  
 

 
   
KEY MESSAGES
 
 
- MUCH COOLER TEMPERATURES WITH BELOW NORMAL READINGS WILL PREVAIL  
DURING THE NEXT COUPLE OF DAYS.  
 
- BREEZY TO LOCALLY WINDY CONDITIONS WILL BE COMMON THROUGH TUESDAY  
WITH MODEST RAIN CHANCES ACROSS THE ARIZONA HIGH TERRAIN AREAS.  
 
- A RAPID WARMING TREND TO ABOVE NORMAL TEMPERATURES IS LIKELY BY  
THE LATTER HALF OF THE WEEK.  
 

 
   
SHORT TERM /TODAY THROUGH TUESDAY/
 
 
THE LATEST WATER VAPOR SATELLITE IMAGERY AS WELL AS STREAMLINE  
ANALYSIS SHOW A RATHER POTENT CUT-OFF LOW SITUATED JUST OFF THE  
CENTRAL CA COAST WITH A LARGE STREAM OF MID TO HIGH-LEVEL CLOUDINESS  
MOVING THROUGH THE DESERT SOUTHWEST. THE CUT-OFF LOW WILL CONTINUE  
TO SLOWLY MIGRATE INLAND LATER TODAY THROUGH CENTRAL CA BEFORE  
MOVING SOUTHEASTWARD THROUGH SOUTHERN CA AND AZ DURING THE DAY  
TUESDAY AS AN OPEN WAVE. AS THE LOW CONTINUES TO SLOWLY APPROACH  
THE REGION, 500 MB HEIGHT FIELDS WILL CONTINUE TO DECREASE INTO  
THE 568-574DM RANGE AND COMBINED WITH THICK MID TO UPPER-LEVEL  
CLOUDINESS, LIMITING THE SOLAR RADIATION, AFTERNOON HIGH  
TEMPERATURES WILL BE A GOOD 10-15 DEGREES COOLER COMPARED TO  
YESTERDAY AS READINGS ACROSS MOST OF THE LOWER DESERT COMMUNITIES  
ONLY TOP OUT IN THE LOW 80S. THESE TEMPERATURES WILL BE A GOOD  
5-10F BELOW NORMAL FOR EARLY MAY. THE ADDITIONAL HEIGHT FALLS AND  
ENHANCED JET ENERGY WILL CONTINUE TO ENHANCE THE LOWER  
TROPOSPHERIC WINDS. HOWEVER, THE THICKER CLOUD COVER MAY TEMPER  
THE OVERALL MIXING DEPTH AND THUS THE ABILITY FOR THE HIGHER  
MOMENTUM AIR TO FULLY MIX DOWN TO THE SURFACE. THUS, EVEN THOUGH  
SOME GUSTY WINDS ARE LIKELY TO MATERIALIZE THIS AFTERNOON/EVENING,  
IT WILL LIKELY NOT BE AS STRONG AS YESTERDAY WITH MANY AREAS  
LIKELY OBSERVING GUSTS BETWEEN 20-30 MPH. SOME LOCALLY HIGHER  
GUSTS IN EXCESS OF 30-35 MPH WILL ONCE AGAIN BE POSSIBLE ACROSS  
WESTERN PORTIONS OF IMPERIAL COUNTY DUE TO MOUNTAIN ROTOR ACTION.  
CANNOT RULE OUT TEMPORARY GUSTS EXCEEDING 40 MPH ACROSS THE WIND  
PRONE AREAS OF SOUTHWESTERN IMPERIAL COUNTY.  
 
AS THE LOW CONTINUES TO SLOWLY MIGRATE EASTWARD FROM THE EASTERN  
PACIFIC, A PLUME OF SUBTROPICAL MOISTURE OUT AHEAD OF THE FEATURE  
WILL BE ADVECTED INTO SOUTHERN AND EASTERN AZ LATER TODAY. THE  
LATEST MODEL GUIDANCE HAS CONTINUED THE UPTREND IN MOISTURE LEVELS  
AS PWATS ARE NOW SHOWN TO PEAK TO BETWEEN 0.8-1.0". THIS MOISTURE  
COMBINED WITH THE LARGE FORCING FOR ASCENT FROM THE LOW WILL  
RESULT IN AN AREA OF LIGHT SHOWERS TO BREAK OUT THIS EVENING  
THROUGH THE OVERNIGHT PERIOD ACROSS PORTIONS OF SOUTHEAST AZ  
AS WELL AS ACROSS THE FOOTHILLS AND THE HIGHER TERRAIN AREAS TO  
SOUTH AND EAST OF PHOENIX AS DEPICTED BY THE LATEST HI-RES  
GUIDANCE. IT IS NOT INCONCEIVABLE TO EVEN SEE SOME RAIN DROPS  
MAKING IT TO THE SURFACE ACROSS THE GREATER PHOENIX AREA. ACTIVITY  
WILL CONTINUE TO AFFECT THE HIGHER TERRAIN AREAS TO THE NORTH AND  
EAST OF PHOENIX INTO THE FIRST PART OF TUESDAY. OVERALL RAINFALL  
AMOUNTS SHOULD REMAIN ON THE LIGHT SIDE, WITH MOST AREAS OBSERVING  
LESS 0.10". OTHERWISE, AS THE COLD CORE MOVES DIRECTLY OVERHEAD  
ON TUESDAY AFTERNOON, HIGH TEMPERATURES ACROSS MOST OF THE LOWER  
DESERT COMMUNITIES WILL STRUGGLE TO REACH 80 DEGREES WITH MANY  
AREAS TOPPING OUT IN THE UPPER 70S, WHICH WILL BE A SOLID 10-15F  
BELOW NORMAL.  
 

 
   
LONG TERM /WEDNESDAY THROUGH SATURDAY/
 
 
THE PRIMARY ENERGY FROM THE LOW WILL EXIT TO THE NORTHEAST AND GET  
ABSORBED BY ANOTHER BROAD TROUGH ENCOMPASSING MOST OF THE CENTRAL  
AND EASTERN CONUS ON WEDNESDAY. MEANWHILE, A TRAILING PIECE OF  
ENERGY WILL DEVELOP INTO A WEAK CUT-OFF LOW JUST SOUTH OF THE  
INTERNATIONAL BORDER IN NORTHERN SONORA AS AN UPPER-LEVEL RIDGE OF  
HIGH PRESSURE BUILDS ALONG THE WEST COAST. ALTHOUGH THERE  
CONTINUES TO SOME UNCERTAINTY WITH RESPECT TO THE SPEED  
PROGRESSION OF THIS FEATURE AS IT CUTS OFF FROM THE MAIN JET  
STREAM ENERGY, LATEST TRENDS HAS BEEN FOR A FASTER EASTWARD  
PROGRESSION THROUGH THE LATTER HALF OF NEXT WEEK WITH NO SENSIBLE  
WEATHER IMPACTS EXPECTED FOR OUR REGION.  
 
OTHERWISE, THE MAIN WEATHER STORY HEADING TOWARDS THE END OF THE  
WEEK AND BEYOND WILL BE THE RISING TEMPERATURES WITH AN EXTENDED  
STRETCH OF TRIPLE DIGIT HIGHS. AS THE UPPER-LEVEL RIDGE GRADUALLY  
BUILDS ACROSS THE WESTERN CONUS BY THE LATTER HALF OF THE WEEK,  
TEMPERATURES WILL BE ON A RAPID WARMING TREND WITH HIGHS BACK UP  
IN THE 90S ON THURSDAY AND INTO TRIPLE DIGITS AS EARLY AS FRIDAY  
AND BEYOND. AS AFTERNOON HIGHS CLIMB INTO THE TRIPLE DIGITS, THE  
OVERALL HEATRISK LEVEL ACROSS MOST OF THE AREA WILL INCREASE INTO  
THE MODERATE CATEGORY.  
 

 
   
AVIATION
 
UPDATED AT 1126Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED THROUGH THE TAF PERIOD.  
WIND GUSTS HAVE CALMED CONSIDERABLY COMPARED TO YESTERDAY, BUT  
SUSTAINED WINDS WILL REMAIN ELEVATED, IN THE MID TEENS, THROUGHOUT  
THE THE PERIOD. WHILE NO PREVAILING INCLUDE GUSTS, PERIODIC GUSTS  
CAN STILL BE POSSIBLE AROUND 20KTS, MOSTLY LATE THIS AFTERNOON  
INTO THE EVENING HOURS. WESTERLY TO SOUTHWESTERLY WINDS WILL BE  
DOMINANT TODAY. CLOUD LEVELS WILL SLOWLY DROP THROUGHOUT THE  
PERIOD, HOWEVER SHOULD REMAIN ABOVE VFR CONDITIONS. THERE IS THE  
POSSIBILITY OF SHOWERS DEVELOPING BY LATE TONIGHT INTO TUESDAY  
MORNING, BUT ARE EXPECTED TO REMAIN MOSTLY TO THE EAST OF THE  
TERMINALS. THE MOST LIKELY TERMINAL TO ANY RAINFALL WILL BE KIWA  
SO MENTION OF VCSH HAS BEEN ADDED TO THE TAF. IT IS NOT OUT OF THE  
QUESTION THE OTHER TERMINALS MAY SEE SOME WEAK ECHOES/VIRGA, BUT  
CHANCES ARE TOO LOW TO INCLUDE MENTION OF ANY VCSH/SHRA AT THESE  
SITES AT THIS TIME.  
 
SLANTWISE VIS/HAZY CONDITIONS WILL LIKELY CONTINUE TO BE A  
CONCERN DUE TO THE BRUSH FIRE IN BUCKEYE. THIS CONTINUES TO BE A  
CONCERN AS OVERNIGHT WINDS TOOK AN UNEXPECTED SHIFT OUT THE WEST  
AND IS EXPECTED TO PREVAIL, SO OPERATIONAL IMPACTS, MAINLY AT  
KSDL AND KDVT CANNOT BE RULED OUT.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
BREEZY TO WINDY CONDITIONS WILL CONTINUE BE THE MAIN AVIATION  
CONCERN DURING THE NEXT 24 HOURS. AT KIPL, GUSTS BETWEEN 25-35 KTS  
ARE EXPECTED TO CONTINUE THROUGHOUT THE TAF PERIOD WITH SUSTAINED  
WIND SPEEDS BETWEEN 15-25 KTS, FROM THE WEST. WITH THESE WINDS,  
BLOWING/LOFTED DUST AROUND THE KIPL TERMINAL MAY BE POSSIBLE,  
LEADING TO CONCERNS OF REDUCED SURFACE AND SLANTWISE VIS. AT BLH,  
GUSTS WILL BE SLIGHTLY LIGHTER IN COMPARISON, HOWEVER, SUSTAINED  
WINDS WILL REMAIN ELEVATED AND GUSTS BETWEEN 20-25 KTS WILL  
DEVELOP BY LATE THIS MORNING, LASTING THROUGH THE AFTERNOON AND  
EVENING. BKN-0VC SKIES WILL BE COMMON THROUGH MOST OF THE PERIOD.  
 

 
   
FIRE WEATHER
 
 
SOME GUSTY WINDS WILL CONTINUE TO REMAIN THREAT THROUGH TUESDAY AS  
AN AREA OF LOW PRESSURE APPROACHES AND MOVES THROUGH THE REGION,  
WITH ONLY A LOCALLY ELEVATED FIRE DANGER THREAT EXPECTED AS HIGHER  
HUMIDITIES WILL LIMIT A GREATER RISK. SOME MODEST RAIN CHANCES  
WILL BE IN PLACE, MAINLY ACROSS THE FAR EASTERN DISTRICTS, LATE  
TODAY THROUGH TUESDAY MORNING WITH THE CHANCES FOR WETTING RAINS  
REMAINING ON THE LOW SIDE. AFTERNOON MINRHS BETWEEN 15-25% WILL BE  
COMMON TODAY BEFORE INCREASING INTO A 20-35% RANGE TUESDAY ALONG  
WITH GOOD OVERNIGHT RECOVERIES. LIGHTER WINDS AS WELL AS MUCH  
WARMER TEMPERATURES AND LOWER HUMIDITIES ARE THEN FORECAST FOR THE  
LATTER HALF OF THE WEEK.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...NONE.  
CA...WIND ADVISORY UNTIL 8 AM PDT THIS MORNING FOR CAZ562.  
 

 
 

 
 
SHORT TERM...LOJERO  
LONG TERM...LOJERO  
AVIATION...RYAN/RW  
FIRE WEATHER...LOJERO  
 
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