303  
FXUS65 KPSR 210522  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1022 PM MST SAT JUN 20 2026  
   
UPDATE...UPDATED 06Z AVIATION DISCUSSION
 
 

 
   
KEY MESSAGES
 
 
- TEMPERATURES WILL REMAIN NEAR SEASONAL LEVELS THROUGH MONDAY  
UNDER CLEAR TO MOSTLY CLEAR SKIES.  
 
- STRONG HIGH PRESSURE WILL BUILD BACK INTO THE REGION BY THE  
MIDDLE OF THE UPCOMING WORK WEEK, PUSHING DAYTIME HIGHS TO  
AROUND OR JUST ABOVE 110 DEGREES ACROSS THE LOWER DESERTS.  
 
- MINOR TO MODERATE HEAT RISK THROUGH EARLY NEXT WEEK WILL BECOME  
WIDESPREAD MODERATE TO LOCALIZED MAJOR HEAT RISK DURING THE  
LATTER HALF OF THE WEEK.  
 

 
   
SHORT TERM /TODAY THROUGH SUNDAY/
 
 
VERY DRY AND SEASONABLY HOT CONDITIONS WILL BE THE MAIN STORY  
THROUGH THE REST OF THE WEEKEND. MOISTURE HAS EFFECTIVELY BEEN  
SCOURED OUT OF THE COLUMN OVER THE LAST COUPLE DAYS THANKS TO  
ENHANCED, DEEP SOUTHWESTERLY FLOW, WITH THE 12Z KPSR SOUNDING THIS  
MORNING ESTIMATING PWAT JUST UNDER 0.5" AND A NOTABLE INVERSION  
BETWEEN 700-500 MB, INDICATIVE OF SYNOPTIC SCALE SUBSIDENCE.  
ACROSS THE FORECAST AREA, DEWPOINT TEMPERATURES IN THE 20S AND 30S  
F HAVE BECOME COMMONPLACE AND WILL PERSIST INTO EARLY NEXT WEEK.  
THE UPPER LEVEL PATTERN IS CHARACTERIZED BY A SOMEWHAT PROGRESSIVE  
NORTHERN STREAM, WITH TROUGHING OVER THE NORTHWEST US. TO THE  
SOUTH, MIDLEVEL WATER VAPOR IMAGERY AND 500 MB RAP ANALYSIS  
INDICATE A SUBTROPICAL HIGH/ANTICYCLONIC FLOW, STRETCHING FROM OFF  
THE NORTHERN BAJA ALL THE WAY THROUGH WESTERN TX AND THE TX  
PANHANDLE. ENSEMBLES REMAIN IN EXCELLENT AGREEMENT THAT THE  
SUBTROPICAL HIGH AND ASSOCIATED HEIGHTS ALOFT WILL REMAIN  
SUPPRESSED AS THE NORTHERN STREAM TROUGHING PROGRESSES INTO THE  
NORTHERN PLAINS THIS WEEKEND. AS A RESULT, RATHER STABLE H5  
HEIGHTS IN A 588-591 DAM RANGE WILL PREVAIL THROUGH SUNDAY,  
REPRESENTING VALUES BETWEEN THE 70TH-90TH PERCENTILE OF  
CLIMATOLOGY. DESPITE THE POSITIVE MIDLEVEL HEIGHT ANOMALIES, VERY  
DRY CONDITIONS AND CLEAR TO MOSTLY CLEAR SKIES WILL PROVIDE FOR  
EFFECTIVE RADIATIVE COOLING OVERNIGHT, LEADING TO WIDESPREAD EARLY  
MORNING LOWS IN THE 70S (NEAR TO SLIGHTLY BELOW NORMALS).  
AFTERNOON HIGHS ARE EXPECTED TO REACH A NEAR NORMAL RANGE, AROUND  
105F FOR THE TYPICALLY HOTTER LOWER DESERT LOCALES.  
 

 
   
LONG TERM /MONDAY THROUGH FRIDAY/
 
 
BY MONDAY, THE BROAD TROUGH SITUATED TO OUR NORTH IS FORECAST TO  
EJECT INTO THE CENTRAL PLAINS FOLLOWED BY THE SUBTROPICAL HIGH  
OVER NORTHERN MEXICO STARTING TO SHIFT NORTHWARD INTO OUR REGION.  
MONDAY WILL BE SOMEWHAT OF A TRANSITION DAY WITH HEIGHTS RISING TO  
592-594DM AS THE HIGH CENTER NEARS SOUTHWEST NEW MEXICO AND OUR  
FLOW ALSO SHIFTS OUT OF THE SOUTH. FORECAST HIGHS RISE MORE INTO  
A 105-109 DEGREE RANGE MONDAY WHILE THE FIRST GULF MOISTURE SURGE  
PUSHES SURFACE DEW POINTS OUT OF THE 20S.  
 
GUIDANCE THEN SHOWS THE CENTER OF THE RIDGE SHIFTING ALONG THE  
SOUTHERN BORDER OF ARIZONA/NEW MEXICO TUESDAY INTO WEDNESDAY WITH  
HEIGHTS RISING MORE INTO A 594-596DM RANGE BY WEDNESDAY. THE  
POSITION OF THE HIGH WILL HELP TO BRING ADDITIONAL GULF MOISTURE  
SURGES INTO MIDWEEK, LIKELY RAISING SURFACE DEW POINTS INTO THE  
LOW 40S TO LOW 50S TUESDAY AND UPPER 40S TO MID 50S WEDNESDAY.  
THIS IS A SLIGHT IMPROVEMENT FROM WHAT MODELS SHOWED 24 HOURS AGO  
AND NOW MAY BE ENOUGH FOR AN INTRODUCTION OF LOW-END POP CHANCES  
ONLY WITHIN HIGHER TERRAIN AREAS. THE NBM DOES NOT REALLY DEPICT  
THESE CHANCES, BUT IF THE MOISTURE FORECAST HOLDS WE MAY INTRODUCE  
SOME ISOLATED 10-15% POPS FOR HIGHER TERRAIN LOCATIONS IN  
SOUTHWEST AND SOUTH-CENTRAL ARIZONA ON TUESDAY AND/OR WEDNESDAY.  
THE MOISTURE MAY END UP BEING ENOUGH FOR CONVECTION, BUT WITH THE  
RIDGE BASICALLY BEING RIGHT OVERHEAD THE SUBSIDENCE WILL LIKELY  
INHIBIT CONVECTION A GOOD AMOUNT. AS OF RIGHT NOW, THE MOISTURE  
ONLY LOOKS TO LAST THROUGH AROUND WEDNESDAY OR AT THE LATEST  
THURSDAY AS DRIER WESTERLY FLOW IS SUGGESTED AGAIN LATE NEXT WEEK.  
 
TEMPERATURES WILL CONTINUE TO HEAT UP THROUGH THE MIDDLE PART OF  
NEXT WEEK AS THE RIDGE STRENGTHENS AND SHIFTS INTO OUR REGION. NBM  
FORECAST HIGHS REACH NEAR 110 DEGREES TUESDAY LEADING TO A  
WIDESPREAD MODERATE HEATRISK BEFORE LIKELY PEAKING CLOSER TO 115  
DEGREES ON THURSDAY. LOCALIZED AREAS OF MAJOR HEATRISK BEGIN TO  
SHOW UP ON WEDNESDAY AS HIGHS REACH 110-113 DEGREES, BUT MORE SO  
ON THURSDAY WITH FORECAST HIGHS BETWEEN 112-115 DEGREES.  
FORTUNATELY, GUIDANCE SHOWS ANOTHER TROUGH MOVING INTO THE  
NORTHWESTERN U.S. WEDNESDAY INTO THURSDAY BEFORE SHIFTING MORE  
INTO CALIFORNIA AND THE GREAT BASIN FRIDAY INTO NEXT WEEKEND. AS A  
RESULT, TEMPERATURES ARE EXPECTED TO BEGIN TO LOWER STARTING  
FRIDAY, BUT THE 110 DEGREE DAYS MAY STILL HOLD ON INTO SATURDAY.  
 

 
   
AVIATION
 
UPDATED AT 0520Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION WEATHER CONCERNS EXPECTED THROUGHOUT THE TAF PERIOD.  
THE OVERALL WIND PATTERN WILL FOLLOW THE TYPICAL DIURNAL  
TENDENCIES WITH OVERALL SPEEDS AOB 10 KTS. SOME OCCASIONAL  
AFTERNOON/EARLY EVENING GUSTS INTO THE MID/UPPER TEENS WILL BE  
POSSIBLE ONCE AGAIN. CLEAR SKIES WILL PERSIST INTO SUNDAY  
AFTERNOON BEFORE SOME HIGH CIRRUS CLOUD DECKS MOVE IN SUNDAY  
EVENING.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION WEATHER CONCERNS EXPECTED THROUGHOUT THE TAF  
PERIOD. AT KIPL, WINDS THROUGH THE OVERNIGHT WILL REMAIN OUT OF  
THE WEST BEFORE SHIFTING OUT OF THE SOUTHEAST SUNDAY MORNING  
THROUGH SUNDAY AFTERNOON AND THEN BACK OUT OF THE WEST SUNDAY  
EVENING. AT KBLH, WINDS WILL GENERALLY FLUCTUATE BETWEEN THE  
SOUTH-SOUTHEAST AND SOUTHWEST. OVERALL WIND SPEEDS WILL GENERALLY  
REMAIN AOB 12 KTS ALONG WITH SOME MINOR AFTERNOON/EVENING  
GUSTINESS.  
 

 
   
FIRE WEATHER
 
 
NEAR NORMAL TEMPERATURES AND VERY DRY CONDITIONS WILL CONTINUE  
THROUGH MONDAY WITH FAIRLY LIGHT WINDS. MINRHS WILL BE IN THE  
SINGLE DIGITS EACH DAY, WHILE OVERNIGHT RECOVERIES WILL BE POOR,  
RANGING BETWEEN 15-35%. SOME AFTERNOON AND EARLY EVENING UPSLOPE  
BREEZINESS WILL BE COMMON, BUT GUSTS WILL MOSTLY STAY BELOW 20  
MPH. THE VERY LOW RHS AND LIGHT BREEZES SHOULD LEAD TO ELEVATED  
FIRE WEATHER CONDITIONS DURING THE LATTER HALF OF THE  
AFTERNOON/EARLY EVENING HOURS. GOING INTO THE MIDDLE PART OF NEXT  
WEEK, MOISTURE WILL IMPROVE RAISING MINRHS TO BETWEEN 10-15% BY  
WEDNESDAY, BUT TEMPERATURES WILL ALSO WARM TO ABOVE NORMAL.  
DAYTIME BREEZINESS SHOULD ALSO INCREASE WITH MORE GUSTS REACHING  
THE 20-25 MPH RANGE.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...NONE.  
CA...NONE.  

 
 

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