596  
FXUS65 KPSR 181129  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
429 AM MST MON MAY 18 2026  
   
UPDATE  
UPDATED AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- A WIND ADVISORY REMAINS IN EFFECT THROUGH 11 AM FOR PORTIONS OF  
SOUTHEAST CALIFORNIA FOR STRONG NORTHERLY POST-FRONTAL WINDS.  
 
- COOLEST TEMPERATURES OVER THE NEXT WEEK AND BEYOND ARE EXPECTED  
TODAY, WITH HIGH TEMPERATURES 4 TO 7 DEGREES BELOW NORMAL,  
BEFORE SLOWLY WARMING BACK UP AND NEARING 100 DEGREE HIGHS  
AGAIN THIS WEEKEND.  
 
- DAILY DRY CONDITIONS, WITH NO THREAT OF RAIN, AND SEASONAL  
AFTERNOON BREEZINESS ARE EXPECTED THROUGH THE NEXT 7 DAYS.  
 
 
   
SHORT TERM /TODAY THROUGH TUESDAY/  
 
A POTENT SHORTWAVE TROUGH WAS SEEN MOVING EASTWARD THROUGH UT  
EARLY THIS MORNING WITH A SOUTHWARD AND SOUTHEASTWARD MOVING COLD  
FRONT THROUGH AZ AND SOCAL. STRONG NORTHERLY WINDS AND WIDESPREAD  
LOFTED DUST WERE OBSERVED POST-FRONT IN SAN BERNARDINO COUNTY.  
THE COLD FRONT WILL CONTINUE DROPPING SOUTH THROUGH SOUTHEAST CA  
AND SOUTHWEST AZ EARLY THIS MORNING, WITH STRONG NORTHERLY POST-  
FRONTAL WINDS EXPECTED THROUGH MID-MORNING. A WIND ADVISORY IS IN  
EFFECT FOR EASTERN RIVERSIDE AND NORTHEAST IMPERIAL COUNTIES  
THROUGH 11 AM PDT/MST THIS MORNING WITH NORTHERLY GUSTS UP TO  
35-50 MPH EXPECTED. LATEST HREF SHOWS STRONGEST 850MB WINDS (>40  
MPH) OCCURRING THROUGH AROUND 3-5 AM PDT/MST THIS MORNING. DURING  
THIS TIME IS WHEN THE GREATEST IMPACTS - PRIMARILY NORTHERLY  
CROSSWINDS ACROSS I-10 AND LOCALIZED BLOWING DUST - ARE  
ANTICIPATED. WHILE THE GRADIENT WIND IS EXPECTED TO WEAKEN AROUND  
THE SUNRISE HOURS, SOME AREAS MAY SEE NORTHERLY WIND GUSTS PICK  
BACK UP FOR A FEW HOURS AFTER SUNRISE DUE TO MIXING. OTHERWISE,  
WINDS SHOULD GRADUALLY SUBSIDE ACROSS SOUTHEAST CA AND SOUTHWEST  
AZ HEADING INTO LATE-MORNING AND THE AFTERNOON. HAZY SKIES SHOULD  
BECOME EVIDENT AFTER SUNRISE THIS MORNING, WITH ALL THE LOFTED  
DUST ACROSS CA AND NV, ESPECIALLY ACROSS SOUTHEAST CA AND  
SOUTHWEST AZ.  
 
HI-RES MODELS DEPICT THE COLD FRONT STALLING OUT ACROSS SOUTH-  
CENTRAL AZ TOWARD SUNRISE AND MID-MORNING. SO, SOUTH-CENTRAL AZ IS  
NOT EXPECTED TO EXPERIENCE ANY OF THE STRONG NORTHERLY AND  
NORTHWESTERLY POST-FRONTAL WINDS. THERE WILL STILL BE SOME BREEZY  
SOUTHWEST WINDS THOUGH LATE MORNING AND THIS AFTERNOON, MOSTLY  
GUSTING UP TO 15-30 MPH. A NARROW BAND OF LOW LEVEL MOISTURE AND  
FORCING ALONG AND AHEAD OF THE FRONT WILL LEAD TO SOME LOWER  
CLOUDS THIS MORNING ACROSS SOUTH-CENTRAL AZ, INCLUDING THE PHOENIX  
AREA, AND A FEW HI-RES MODELS STILL SUPPORT A BRIEF SPRINKLE  
SHOWER. SO, A FEW DROPS FALLING IN THE MORNING, AFTER SUNRISE  
CANNOT BE RULED OUT, BUT DO NOT EXPECT ANY MEASURABLE RAIN.  
 
THE DIP IN 500MB HEIGHTS OVER THE AREA AND PUSH OF COOLER AIR FROM  
THE NORTH WILL RESULT IN COOLER SURFACE TEMPERATURES TODAY, WITH  
BELOW NORMAL HIGH TEMPERATURES EXPECTED ACROSS THE REGION. HIGHS  
THIS AFTERNOON ARE FORECAST TO MOSTLY BE IN THE 80S ACROSS THE  
LOWER DESERTS, WITH ONLY 10-20% CHANCES OF REACHING 90F IN PLACES  
LIKE PHOENIX AND YUMA.  
 
HEADING INTO TOMORROW, THE POTENT TROUGH WILL HAVE LEFT THE  
REGION, EJECTING THROUGH THE PLAINS, BUT ANOTHER TRAILING WEAK  
SHORTWAVE WILL FOLLOW AND KEEP A LARGE-SCALE TROUGH PATTERN IN  
PLACE ACROSS THE DESERT SOUTHWEST. THIS WILL KEEP TEMPERATURES  
FROM RAPIDLY WARMING BACK UP AND WHILE THEY WILL WARM UP FROM  
TODAY, HIGHS TOMORROW ARE STILL FORECAST TO COME UP SHY OF DAILY  
NORMALS. MOST LOWER DESERTS WILL TOP OUT WITH HIGHS IN THE LOWER  
90S. WINDS TOMORROW WILL BE EVEN LIGHTER THAN TODAY FOR MOST  
AREAS. ALTHOUGH, WITH THE TRAILING SHORTWAVE THERE WILL BE ANOTHER  
ENHANCEMENT TO NORTHERLY WINDS DOWN THE COLORADO RIVER AND  
SOUTHEAST CA, WITH PEAK WIND GUSTS AS HIGH AS 20-30 MPH IN THE  
MORNING THROUGH MIDDAY. THE LAGGING SHORTWAVE WILL ALSO HELP DRAW  
SCATTERED HIGH CLOUDS INTO THE DESERT SOUTHWEST THROUGH THE DAY.  
 
 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/  
 
THROUGH THE REST OF THE WEEK, GLOBAL ENSEMBLES DEPICT A LASTING  
WEAK LONGWAVE TROUGH PATTERN ACROSS THE DESERT SOUTH, WITH NEUTRAL  
HEIGHT ANOMALIES AND NO SIGNIFICANT SHORTWAVES ROLLING THROUGH  
THE REGION. THIS WILL TRANSLATE TO RATHER SEASONAL WEATHER  
CONDITIONS, BUT WITH A SLOW DAY-TO-DAY WARMING TREND. HIGH  
TEMPERATURES ARE FORECAST TO BE NEAR NORMAL THROUGH THE END OF THE  
WORK WEEK - HIGHS IN THE MIDDLE TO UPPER 90S. MEANWHILE MORNING  
LOWS ARE EXPECTED TO BE NEAR TO SLIGHTLY BELOW NORMAL, LARGELY DUE  
TO DRY AIR/LOW HUMIDITY AND LIMITED CLOUD COVER. IT IS NOT UNTIL  
THE WEEKEND WHEN ODDS OF HIGH TEMPERATURES REACHING THE 100 DEGREE  
MARK SPIKES BACK UP TO AROUND 30-60%, AS THE LONGWAVE TROUGH  
ACROSS THE DESERT SOUTHWEST BREAKS DOWN. CONDITIONS WILL REMAIN  
DRY THROUGH THIS WEEKEND, WITH NO THREAT OF RAIN, AND SEASONAL  
WIND PATTERNS ARE EXPECTED, WITH LIGHT WINDS THROUGH THE OVERNIGHT  
AND MORNING HOURS AND AFTERNOON UPSLOPE BREEZES UP TO 15-25 MPH.  
 
 
   
AVIATION  
UPDATED AT 1120Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
 
LOW CONFIDENCE ON WIND DIRECTIONS EARLY THIS MORNING AND THE  
POTENTIAL FOR A FEW-SCT DECK AS LOW AS 4 KFT AGL BETWEEN NOW AND  
17Z ARE THE MAIN CONCERNS THROUGH THE TAF PERIOD UNDER OTHERWISE  
MOSTLY CLEAR SKIES. THERE IS A LOW PROBABILITY OF SLANTWISE VIS  
RESTRICTIONS AROUND SUNRISE AND 20-40% PROBABILITY OF BRIEF CIGS  
AROUND 040-050 ONLY FOR KDVT (JUST NORTH OF THE PHOENIX AIRSPACE).  
S- SW WINDS MAY PERSIST THROUGH THE MORNING, THOUGH A BRIEF  
PERIOD OF VARIABILITY OR RELATIVELY LIGHT SE WINDS FOR A FEW HOURS  
AROUND SUNRISE CANNOT BE RULED OUT. SW WINDS WILL ESTABLISH AND  
INCREASE LATE MORNING TO AROUND 10 KTS, WITH GUSTS INTO THE MID TO  
UPPER TEENS LIKELY TO DEVELOP THIS AFTERNOON. A MORE TYPICAL  
NOCTURNAL SE WIND SHIFT IS ANTICIPATED TONIGHT.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
GUSTY NORTH NORTHWEST WINDS AND SLANTWISE VIS RESTRICTIONS AROUND  
SUNRISE DUE TO LOFTED DUST/HAZE WILL BE THE ONLY WEATHER ISSUES  
THROUGH THE NEXT 24 HOURS UNDER MOSTLY CLEAR SKIES. A PERIOD WITH  
STRONGER GUSTS (25-30 KTS) WILL BE POSSIBLE AT KBLH BETWEEN  
14-18Z, BUT OTHERWISE GUSTS WILL MOSTLY PEAK AROUND 20-25 KTS AND  
SUBSIDE BY THE EVENING. OCCASIONAL GUSTS TO AROUND 20 KTS MAY BE  
OBSERVED AT KIPL THIS MORNING. SPEEDS WILL DIMINISH AT BOTH SITE  
THROUGH THE AFTERNOON, WITH DIRECTIONS BACKING OUT OF THE W-NW  
THIS EVENING.  
 
 
   
FIRE WEATHER  
 
ELEVATED AND MARGINALLY CRITICAL FIRE WEATHER CONDITIONS ARE  
EXPECTED EARLY THIS MORNING ACROSS PORTIONS OF SOUTHEAST CA AS A  
RESULT OF STRONG NORTHERLY WINDS AND DRY AIR FOLLOWING A FRONTAL  
PASSAGE. CONDITIONS WILL IMPROVE BY LATE-MORNING/EARLY-AFTERNOON  
AS NORTHERLY WINDS SUBSIDE. ELSEWHERE TODAY, WINDS WILL BE  
LIGHTER, BUT STILL WITH PEAK SOUTHWESTERLY GUSTS UP TO 15-30 MPH  
ACROSS SOUTH-CENTRAL AZ. MINIMUM RH VALUES TODAY WILL BE AROUND  
5-10% ACROSS WESTERN DISTRICTS TO 15-25% ACROSS EASTERN DISTRICTS.  
TEMPERATURES WILL BE COOLEST, AND BELOW NORMAL, TODAY, WHICH WILL  
RESULT LOWER MAX MIXING HEIGHTS (UP TO 6-8K FT ABOVE GROUND  
LEVEL). TEMPERATURES WILL SLOWLY WARM THROUGH THE END OF THE WEEK,  
BUT REMAIN NEAR SEASONAL LEVEL, AND CONDITIONS WILL REMAIN DRY.  
DAILY MINIMUM RH VALUES WILL BE AROUND 5-15% EACH DAY AFTER TODAY  
WITH POOR TO FAIR OVERNIGHT RECOVERIES AT 25-50%. AFTER TODAY SEASONAL  
WIND PATTERNS ARE EXPECTED THROUGH THE REST OF THE WEEK, WITH  
AFTERNOON UPSLOPE BREEZES UP TO 15-25 MPH AND THE ONLY EXCEPTION  
BEING ANOTHER BRIEF ENHANCED NORTHERLY WIND DOWN THE COLORADO  
RIVER TOMORROW MORNING. THERE IS NO RAIN IN THE FORECAST THROUGH  
THIS WEEKEND.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...WIND ADVISORY UNTIL 11 AM PDT THIS MORNING FOR CAZ560-561-564-  
568>570.  
 
 
 
 
 
SHORT TERM...BENEDICT  
LONG TERM...BENEDICT  
AVIATION...WHITTOCK  
FIRE WEATHER...BENEDICT  
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