569  
FXUS65 KPSR 130515  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1015 PM MST TUE MAY 12 2026  
   
UPDATE...UPDATED 06Z AVIATION DISCUSSION
 
 

 
   
KEY MESSAGES
 
 
- TEMPERATURES WILL COOL A FEW MORE DEGREES THE REST OF THE WEEK,  
HOWEVER REMAIN IN A SLIGHTLY ABOVE NORMAL RANGE.  
 
- BREEZY CONDITIONS WILL DEVELOP ALONG THE LOWER COLORADO RIVER  
VALLEY AND ARIZONA HIGH TERRAIN ON WEDNESDAY, THEN RETURN TO THE  
AREA OVER THE WEEKEND.  
 

 
   
SHORT TERM /TODAY THROUGH THURSDAY/
 
 
EARLY AFTERNOON OBJECTIVE ANALYSIS DEPICTS A 590DM H5 ANTI-CYCLONE  
CENTERED OVER WESTERN NEW MEXICO SLOWLY BEING DISLODGED AND DE-  
AMPLIFIED BY THE COMBINED EFFORT OF SUBTROPICAL ENERGY LIFTING NORTH  
FROM THE BAJA INTO THE SW CONUS AND STRONGER TROUGHING ENTERING THE  
PACIFIC NW. AS SUCH, H5 HEIGHTS WITHIN THE FORECAST AREA HAVE ERODED  
INTO A 584-588DM RANGE PROVIDING SLIGHT COOLING VERSUS YESTERDAY,  
AND MOST PRONOUNCED OVER THE WESTERN CWA. OTHERWISE, ONLY A NARROW  
MIDLEVEL MOISTURE BAND ASSOCIATED WITH BAJA SHORTWAVE WILL PASS  
THROUGH THE REGION WITH SOME VIRGA (AND POSSIBLE ERRATIC WINDS) AS A  
RESULT.  
 
OVER THE NEXT COUPLE DAYS, HIGH PRESSURE ALOFT WILL FURTHER BE  
DISPLACED EASTWARD WITH A PROGRESSIVE FLOW PATTERN RESULTING IN  
ADDITIONAL MODEST HEIGHTS FALLS ACROSS THE SW CONUS. SOME MEASURE OF  
WEAK TROUGHING/QUASI-ZONAL FLOW WILL PREVAIL OVER THE REGION WITH H5  
HEIGHTS GENERALLY HOVERING IN A 580-584DM RANGE. ENSEMBLE GUIDANCE  
SPREAD IS RATHER NARROW LEADING TO EXCELLENT FORECAST CONFIDENCE OF  
HIGH TEMPERATURES MOSTLY 6F-8F ABOVE NORMAL, WHILE CLEAR SKIES AND A  
DRY AIRMASS PROMOTE EFFICIENT NOCTURNAL COOLING AND LOWS NOT FAR  
FROM CLIMATOLOGY. THIS PATTERN OF WEAK TROUGHING/HEIGHT FALLS WILL  
SUPPORT DEEP MECHANICAL MIXING AND GUSTY AFTERNOON WINDS, THOUGH  
NOTHING UNUSUALLY STRONG FOR MID MAY.  
 

 
   
LONG TERM /FRIDAY THROUGH TUESDAY/
 
 
THE WEATHER PATTERN LATER THIS WEEK IS EXPECTED SHIFT TO A MORE  
ZONAL WESTERLY DRY FLOW PATTERN, BUT WITH SOME INFLUENCE FROM  
PASSING TROUGHS TO OUR NORTH. THE DRYING FLOW WILL RESULT IN CLEAR  
TO MOSTLY CLEAR SKIES FRIDAY-SATURDAY WITH TEMPERATURES REMAINING  
QUITE STABLE AVERAGING 5-7 DEGREES ABOVE NORMAL. ENSEMBLES ARE  
CURRENTLY FAVORING A LARGER PACIFIC TROUGH MOVING THROUGH THE  
PACIFIC NORTHWEST THIS WEEKEND BRINGING LOWER HEIGHTS AS FAR SOUTH  
AS THE SOUTHWESTERN U.S. NBM/WPC TEMPERATURE GUIDANCE SUGGESTS  
DAYTIME HIGHS FALLING BACK MORE INTO THE UPPER 90S BY AROUND SUNDAY.  
OTHERWISE, DAYTIME GUSTY WINDS WILL RETURN TO THE REGION OVER THE  
WEEKEND IN ASSOCIATION WITH THE AFOREMENTIONED TROUGH PASSAGE.  
 

 
   
AVIATION
 
UPDATED AT 0510Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
OCCASIONAL GUSTY WINDS UNDER MID/HIGH CLOUD DECKS WILL BE THE  
PRIMARY AVIATION WEATHER ISSUE THROUGHOUT THE TAF PERIOD. CURRENT  
WESTERLY WINDS WILL SWITCH OUT OF THE EAST DURING THE OVERNIGHT  
PERIOD. BEFORE THE TYPICAL WESTERLY SWITCHOVER WEDNESDAY  
AFTERNOON, A PERIOD OF SOUTHERLY CROSSWINDS BETWEEN 8-12 KTS IS  
ANTICIPATED DURING THE LATE MORNING/EARLY AFTERNOON HOURS.  
OCCASIONAL GUSTS UPWARDS OF 20-25 KTS ARE ANTICIPATED ONCE AGAIN  
WEDNESDAY AFTERNOON, STRONGEST NEAR KIWA.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
PERIODS OF GUSTY WINDS UNDER SOME PASSING HIGH CLOUD DECKS WILL BE  
THE PRIMARY AVIATION WEATHER ISSUE THROUGHOUT THE TAF PERIOD. AT  
KIPL, WINDS WILL GENERALLY BE OUT OF THE WEST WHILE AT KBLH, WINDS  
WILL GENERALLY FLUCTUATE BETWEEN THE SOUTH AND SOUTHWEST. WINDS  
DURING THE OVERNIGHT AND MORNING HOURS WILL BE AOB 10 KTS BEFORE  
GUSTS AS HIGH AS 25 KTS ARE EXPECTED AT KBLH DURING THE AFTERNOON  
HOURS AND AT KIPL DURING THE LATE AFTERNOON/EVENING HOURS.  
 

 
   
FIRE WEATHER
 
 
HOT, DRY, AND LOCALLY BREEZY TO WINDY CONDITIONS WILL RESULT IN  
ELEVATED FIRE WEATHER POTENTIAL THIS AFTERNOON ACROSS THE LOWER CO  
RIVER VALLEY. WIND GUSTS OF 20-30 MPH ALONG WITH RHS 7-10% ARE  
EXPECTED ACROSS THE LOWER CO RIVER VALLEY. ELSEWHERE TODAY, WINDS  
WILL BE LIGHTER BUT WITH AFTERNOON GUSTS OF 15-20 MPH POSSIBLE.  
WEDNESDAY WILL BRING ANOTHER ROUND OF BREEZY WINDS OVER SOUTHEAST  
CALIFORNIA AND THE ARIZONA HIGH TERRAIN WITH ELEVATED FIRE WEATHER  
CONDITIONS AGAIN A POSSIBILITY. TEMPERATURES TODAY WILL BE 10-15  
DEGREES ABOVE NORMAL DROPPING TO 5-8 DEGREES ABOVE NORMAL STARTING  
WEDNESDAY. WINDS WILL DIMINISH STARTING THURSDAY, BUT VERY DRY  
CONDITIONS WILL CONTINUE TO PREVAIL.  
 

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

 
 

 
 
SHORT TERM...18  
LONG TERM...KUHLMAN  
AVIATION...LOJERO  
FIRE WEATHER...KUHLMAN  
 
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