639  
FXUS65 KPSR 182350  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
450 PM MST TUE FEB 18 2025  
   
UPDATE
 
UPDATED 00Z AVIATION DISCUSSION.  
 

 
   
SYNOPSIS
 
 
DRY, WARM, AND TRANQUIL WEATHER CONDITIONS WILL BE COMMON DURING  
THE NEXT SEVERAL DAYS. A FEW WEAK WEATHER SYSTEMS WILL BYPASS TO  
THE NORTH OF THE REGION, ONE TODAY AND ANOTHER THURSDAY INTO  
FRIDAY DELIVERING SOME BREEZY CONDITIONS ACROSS THE VICINITY OF  
THE LOWER COLORADO RIVER VALLEY. STRONG HIGH PRESSURE WILL THEN  
BUILD ACROSS THE WESTERN CONUS BY THIS WEEKEND THROUGH AT LEAST  
THE FIRST HALF OF NEXT WEEK, DELIVERING WELL-ABOVE NORMAL  
TEMPERATURES THAT COULD POTENTIALLY PUSH NEAR RECORD TERRITORY.  
 

 
   
DISCUSSION
 
 
LATEST WATER VAPOR SATELLITE IMAGERY REVEALS A WEAK SHORTWAVE TROUGH  
TRAVERSING THE FOUR-CORNERS REGION. THIS SYSTEM WILL NOT RESULT ANY  
NOTICEABLE SENSIBLE WEATHER IMPACTS OTHER THAN PRODUCE SOME BREEZY  
CONDITIONS ALONG THE HIGHER TERRAIN AREAS OF SOUTHEAST CA AND THE  
LOWER COLORADO RIVER VALLEY, WHERE PEAK GUSTS UPWARDS OF 25-30 MPH  
WILL BE POSSIBLE THROUGH THIS AFTERNOON. OTHERWISE, HIGH  
TEMPERATURES WILL CONTINUE TO AVERAGE 5-8 DEGREES ABOVE NORMAL AS  
READINGS TOP OUT IN THE MID TO UPPER 70S ACROSS THE LOWER DESERTS.  
 
AS THE SHORTWAVE TROUGH RAPIDLY SHIFTS EASTWARD, UPPER-LEVEL  
RIDGING WILL BUILD ACROSS THE DESERT SOUTHWEST ON WEDNESDAY. THIS  
WILL RESULT IN SLIGHTLY WARMER DAYTIME HIGH TEMPERATURES AS  
READINGS REACH THE UPPER 70S WITH SOME AREAS APPROACHING 80  
DEGREES ACROSS THE LOWER DESERTS WITH SIMILAR READINGS EXPECTED ON  
THURSDAY. THE RIDGING WILL THEN TEMPORARILY BREAK DOWN LATER  
THURSDAY THROUGH FRIDAY AS ANOTHER WEAK SHORTWAVE TROUGH WILL  
TRAVERSE THE FOUR CORNERS REGION. THIS SYSTEM SIMILAR TO THE  
SYSTEM PASSING THROUGH TODAY WILL NOT RESULT IN MUCH IN THE WAY OF  
SIGNIFICANT SENSIBLE WEATHER IMPACTS OTHER THAN PRODUCE BREEZY TO  
LOCALLY WINDY CONDITIONS ALONG THE VICINITY OF THE LOWER COLORADO  
RIVER VALLEY AREA, MAINLY FOR FRIDAY, AS GUSTS COULD REACH AS  
HIGH 30-35 MPH IN SOME AREAS. THESE ELEVATED GUSTS IN COMBINATION  
WITH LOW MINRHS AND DRY FUELS COULD ACTUALLY LEAD TO LOCALLY  
ELEVATED FIRE WEATHER CONDITIONS. OTHERWISE, NOT MUCH CHANGE IN  
THE TEMPERATURES ARE EXPECTED AS HIGHS WILL CONTINUE TOP OUT IN  
THE UPPER 70S ACROSS MOST OF THE LOWER DESERTS.  
 
STRONG CONSENSUS CONTINUES AMONGST THE ENSEMBLES OF STRONG  
RIDGING BUILDING OVERHEAD HEADING INTO THE WEEKEND THROUGH MOST OF  
NEXT WEEK. THIS RIDGING WILL KEEP DRY AND TRANQUIL WEATHER  
CONDITIONS IN PLACE. THE BIG STORY WILL BE THE POTENTIAL FOR NEAR  
RECORD HIGH TEMPERATURES TO MATERIALIZE, ESPECIALLY DURING THE  
EARLY TO MIDDLE PORTION OF NEXT WEEK. WITH 500 MB HEIGHT FIELDS  
LIKELY TO APPROACH/EXCEED 580DM, HIGH TEMPERATURES ARE LIKELY TO  
TOP OUT IN THE MID TO UPPER 80S ACROSS MOST OF THE LOWER DESERTS  
STARTING ON SUNDAY. THERE IS EVEN A DECENT SHOT (30-60% BASED ON  
THE LATEST NBM) FOR SEVERAL OF THE LOWER DESERT LOCATIONS TO  
APPROACH 90 DEGREES FOR THE FIRST TIME THIS YEAR, WITH THE BEST  
POTENTIAL AT THIS TIME APPEARING TO BE TUESDAY AND WEDNESDAY OF  
NEXT WEEK. TEMPERATURES REACHING 90+ DEGREES WOULD BE QUITE  
UNUSUAL FOR FEBRUARY GIVEN THAT THE AVERAGE FIRST 90 DEGREE DAY  
FOR YUMA AND EL CENTRO DOES NOT OCCUR UNTIL LATE MARCH AND FOR  
PHOENIX NOT UNTIL EARLY APRIL.  
 

 
   
AVIATION
 
UPDATED AT 2350Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT; AND  
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
WINDS WILL TEND TO FOLLOW THEIR TYPICAL DIURNAL TENDENCIES AT ALL  
TERMINALS. WIND GUSTS INTO THE UPPER TEENS WILL CONTINUE AT KBLH  
UNTIL AROUND 01Z WHEN THEY WILL START TO TAPER OFF. AT ALL OTHER  
TERMINALS, AND AFTER 01Z AT KBLH, WIND SPEEDS WILL GENERALLY BE  
AOB 7 KT THROUGH THE TAF PERIOD. HIGH CIRRUS CLOUDS WILL INCREASE  
IN COVERAGE ACROSS THE REGION TONIGHT.  
 

 
   
FIRE WEATHER
 
 
DRY CONDITIONS, WITH MINRH VALUES GENERALLY IN THE MIDDLE TO UPPER  
TEENS, WILL PERSIST THROUGH THE END OF THE WORKWEEK. WINDS ACROSS  
MOST OF THE DISTRICTS WILL FOLLOW LIGHT AND DIURNAL TRENDS OVER  
THE NEXT FEW DAYS, WITH THE ONE EXCEPTION BEING THIS AFTERNOON  
ACROSS PARTS OF THE WESTERN DISTRICTS WHERE MARGINAL BREEZINESS  
(25-30 MPH) WILL DEVELOP. AS ANOTHER DRY WEATHER SYSTEM BYPASSES  
TO THE NORTH LATE THIS WEEK, ANOTHER ROUND BREEZY TO LOCALLY  
WINDY CONDITIONS SHOULD BE ANTICIPATED FOR THESE SAME AREAS,  
LEADING TO LOCALLY ELEVATED FIRE WEATHER CONDITIONS. TEMPERATURES  
WILL REMAIN 5-10 DEGREES ABOVE-NORMAL INTO THIS WEEKEND.  
 

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

 
 

 
 
DISCUSSION...LOJERO  
AVIATION...BERISLAVICH  
FIRE WEATHER...RW/LOJERO  
 
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