549  
FXUS65 KPSR 021111  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
411 AM MST SAT MAY 2 2026  
   
UPDATE  
12Z AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- ABOVE NORMAL TEMPERATURES WITH LOWER DESERT HIGHS IN THE MIDDLE  
NINETIES WILL BE COMMON THROUGHOUT THE WEEKEND.  
 
- AS A LOW PRESSURE SYSTEM APPROACHES THE REGION EARLY NEXT WEEK,  
BREEZY TO LOCALLY WINDY CONDITIONS, MUCH COOLER TEMPERATURES,  
AND INCREASED RAIN CHANCES ACROSS THE AZ HIGH TERRAIN CAN BE  
EXPECTED.  
 
- AS THE LOW PRESSURE SYSTEM DEPARTS THE REGION AND HIGH PRESSURE  
BUILDS IN BY THE LATTER HALF OF NEXT WEEK, A RAPID WARMING  
TREND TO ABOVE NORMAL TEMPERATURES IS LIKELY.  
 
 
   
SHORT TERM /TODAY THROUGH MONDAY/  
 
EARLY MORNING WATER VAPOR SATELLITE AS WELL AS STREAMLINE ANALYSIS  
SHOW A RIDGE OF HIGH PRESSURE ENVELOPING THE WESTERN CONUS WHILE AN  
UPPER-LEVEL LOW IS PIVOTING OFF THE WEST COAST. MEANWHILE TO THE  
EAST, A LONGWAVE TROUGH IS ENVELOPING MOST OF THE EASTERN HALF OF  
CONUS WITH A TRAILING SHORTWAVE ENVELOPING EASTERN AZ AND NM,  
RESULTING IN A FEW LIGHT SHOWERS ACROSS FAR EASTERN AZ. AS HEIGHTS  
ALOFT INCREASE TO 576-578DM FROM THE RIDGE ENVELOPING THE WESTERN  
CONUS, AFTERNOON HIGH TEMPERATURES BOTH TODAY AND SUNDAY WILL TOP  
OUT IN THE MIDDLE 90S ACROSS MOST OF THE LOWER DESERT LOCATIONS. AS  
SURFACE HIGH PRESSURE BUILDS ALONG THE SOUTHERN PLAINS, AN EASTERLY  
GRADIENT WILL SETUP THIS MORNING AND TO A LESSER EXTENT ON SUNDAY  
MORNING, PRODUCING SOME GUSTY WINDS AFTER SUNRISE AS PEAK GUSTS  
REACH 15-25 MPH ACROSS THE LOWER ELEVATIONS OF SOUTH-CENTRAL AZ AND  
LOCALLY HIGHER UPWARDS OF 30-35 MPH ACROSS THE HIGHER TERRAIN AREAS  
EAST OF PHOENIX.  
 
THE AFOREMENTIONED UPPER-LEVEL LOW OFF THE WEST COAST WILL  
CONTINUE TO DIG SOUTHWARD AND BECOME CUTOFF OFF THE CA COAST LATER  
TODAY. AS THE LOW SLOWLY MIGRATES EASTWARD ON SUNDAY, GRADUAL  
HEIGHT FALLS WILL LEAD TO AN INCREASE IN BREEZY TO LOCALLY WINDY  
CONDITIONS ACROSS SOUTHWEST AZ AND SOUTHEAST CA, WHERE  
AFTERNOON/EVENING GUSTS BETWEEN 25-35 MPH WILL BE COMMON. LOCALLY  
HIGHER GUSTS IN EXCESS OF 40 MPH ARE LIKELY ACROSS THE TYPICALLY  
WIND PRONE AREAS OF SOUTHWESTERN IMPERIAL COUNTY.  
 
HEADING INTO MONDAY, THE UPPER LOW WILL GRADUALLY MOVE INLAND  
THROUGH CA. WITH 500 MB HEIGHT FIELDS FALLING TO BETWEEN 568-572DM,  
TEMPERATURES WILL COOL RATHER SIGNIFICANTLY AS AFTERNOON HIGHS WILL  
ONLY TOP OUT IN THE LOWER 80S ACROSS THE WESTERN DESERTS TO MIDDLE  
80S ACROSS THE SOUTH-CENTRAL AZ LOWER DESERTS. WITH THE HEIGHT  
FALLS AND ASSOCIATED JET ENERGY SPREADING EASTWARD, THE  
AFTERNOON/EARLY EVENING BREEZINESS WILL BECOME MORE WIDESPREAD TO  
INCLUDE MOST OF AZ. ADDITIONALLY, THE SLOW EASTWARD MIGRATION OF  
THE LOW WILL ALLOW SOME MOISTURE TO ADVECT NORTHWARD INTO THE  
EASTERN HALF OF AZ, WITH MODEL GUIDANCE SHOWING PWATS RISING TO  
BETWEEN 0.7-0.8" (~200% OF NORMAL). THEREFORE, THE POTENTIAL WILL  
EXIST FOR SCATTERED LIGHT SHOWERS TO BREAK OUT, ESPECIALLY ACROSS  
THE HIGHER TERRAIN AREAS OF EASTERN AZ, LATE MONDAY NIGHT THROUGH  
THE FIRST PART OF TUESDAY, WITH NBM POPS SOLIDLY INTO THE 20-40%  
RANGE.  
 
 
   
LONG TERM /TUESDAY THROUGH FRIDAY/  
 
AS THE THE UPPER LOW MOVES THROUGH THE DESERT SW ON TUESDAY,  
TEMPERATURES WILL COOL EVEN FURTHER WITH AFTERNOON HIGHS ONLY  
REACHING THE UPPER 70S TO AROUND 80 DEGREES ACROSS THE LOWER  
DESERTS. THIS WILL BE A SOLID 10 DEGREES BELOW NORMAL FOR EARLY  
MAY. BREEZY CONDITIONS WILL ALSO REMAIN IN PLACE ACROSS MUCH OF  
THE REGION. THE LOW WILL FINALLY EXIT TO OUR EAST BY MID WEEK WITH  
UPPER-LEVEL RIDGING BUILDING ALONG THE WEST COAST. THERE ARE  
INDICATIONS FROM GUIDANCE THAT A PIECE OF ENERGY LEFT BEHIND FROM  
THE DEPARTING LOW COULD DEVELOP INTO A WEAK CUTOFF LOW OVER THE  
BAJA PENINSULA HEADING INTO THE LATTER HALF OF THE WEEK, BUT AS OF  
RIGHT NOW IT LOOKS TO BE TOO FAR TO THE SOUTH TO HAVE ANY  
SENSIBLE WEATHER IMPACTS FOR OUR REGION. WITH 500 MB HEIGHT FIELDS  
RAPIDLY RISING TO AROUND 580DM FROM THE BUILDING RIDGE,  
TEMPERATURES BY THE LATTER HALF OF THE WEEK WILL BE ON A RAPID  
WARMING TREND. THE LATEST NBM IS SHOWING AFTERNOON HIGHS ACROSS  
THE LOWER DESERTS RAPIDLY WARMING FROM THE MIDDLE 80S ON WEDNESDAY  
TO MIDDLE 90S ON THURSDAY. EVEN FURTHER WARMING INTO THE TRIPLE  
DIGITS, WHICH WOULD BE THE FIRST OCCURRENCE SINCE THE  
UNPRECEDENTED EARLY SEASON HEATWAVE FROM LATE MARCH, IS BEING  
SHOWN STARTING NEXT FRIDAY.  
 
 
   
AVIATION  
UPDATED AT 1111Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED THROUGH THE TAF PERIOD.  
EASTERLY WINDS WILL PREVAIL THROUGH MOST OF THE TAF PERIOD AS THE  
TYPICAL AFTERNOON WESTERLY SHIFT IS UNLIKELY TO OCCUR TODAY.  
GUSTS UP TO 20-25 KTS WILL BE POSSIBLE LATE THIS MORNING BETWEEN  
14-18Z. WINDS WILL THEN RELAX HEADING INTO THE AFTERNOON AND  
EVENING HOURS. FEW HIGH CLOUDS WILL GRADUALLY INCREASE TO SCT-BKN  
LATER IN THE PERIOD.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED THROUGH THE TAF PERIOD.  
NW/NNW WINDS WILL TRANSITION TO E/NE BY LATE THIS MORNING.  
AFTERWARDS, KIPL WILL BECOME MORE WESTERLY BY LATE THIS EVENING,  
WHILE KBLH WILL GO FROM SSE IN THE AFTERNOON TO SSW CLOSE TO  
MIDNIGHT TONIGHT. WIND SPEEDS AT BOTH TERMINALS SHOULD GENERALLY  
REMAIN AOB 10 KTS. FEW HIGH CLOUDS WILL GRADUALLY INCREASE TO SCT-  
BKN LATER IN THE PERIOD.  
 
 
   
FIRE WEATHER  
 
DRY CONDITIONS AND ABOVE NORMAL TEMPERATURES WILL BE OBSERVED  
THROUGH THE WEEKEND. A LOW PRESSURE SYSTEM WILL GRADUALLY APPROACH  
THE CA COAST LATE THIS WEEKEND, RESULTING IN WIDESPREAD BREEZY TO  
LOCALLY WINDY CONDITIONS INTO EARLY NEXT WEEK AND TEMPERATURES  
COOLING INTO A BELOW NORMAL CATEGORY MONDAY-TUESDAY. GUSTY  
AFTERNOON WINDS COMBINED WITH LOW HUMIDITIES WILL LIKELY PRODUCE  
ELEVATED FIRE WEATHER CONDITIONS SUNDAY FOR PORTIONS OF THE  
WESTERN DISTRICTS, INCLUDING THE LOWER COLORADO RIVER VALLEY. AS  
THE LOW PRESSURE SYSTEM MOVES THROUGH THE DESERT SOUTHWEST EARLY  
NEXT WEEK, THE CHANCE OF SHOWERS WILL INCREASE LATE MONDAY INTO  
THE FIRST PART OF TUESDAY ACROSS THE FAR EASTERN DISTRICTS,  
HOWEVER, THE PROBABILITY OF WETTING RAINS WILL REMAIN ON THE LOW  
SIDE. AFTERNOON MINRHS BETWEEN 8-15% WILL BE COMMON TODAY,  
INCREASING SLIGHTLY INTO A 10-20% RANGE SUNDAY AND 15-30% RANGE  
EARLY NEXT WEEK.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
SHORT TERM...LOJERO  
LONG TERM...LOJERO  
AVIATION...RYAN  
FIRE WEATHER...LOJERO/WHITTOCK  
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