036  
FXUS65 KPSR 091115  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
415 AM MST TUE SEP 9 2025  
   
UPDATE
 
UPDATED AVIATION DISCUSSION  
 

 
   
KEY MESSAGES
 
 
 
- TEMPERATURES WILL STAY WITHIN THE NORMAL RANGE THROUGH MID  
WEEK, RESULTING IN LOCALLY MODERATE HEAT RISK FOR THE LOWER  
DESERTS, BEFORE COOLING SLIGHTLY LATE WEEK.  
 
- OVERALL DRY CONDITIONS ARE EXPECTED FOR THE NEXT 7 DAYS WITH  
ONLY SLIGHT CHANCES FOR RAIN OVER THE EASTERN ARIZONA HIGH  
TERRAIN WEDNESDAY INTO THURSDAY.  
 

 
   
SHORT TERM /TODAY THROUGH WEDNESDAY/
 
 
A DEEP PACIFIC TROUGH REMAINS NEARLY STATIONARY OVER AND OFFSHORE  
OF THE NORTHWESTERN U.S. THE DEEPENING OF THIS TROUGH OVER THE  
PAST DAY OR SO HAS LED TO A SLIGHTLY HIGHER AMPLITUDE SUBTROPICAL  
RIDGE INTO THE DESERT SOUTHWEST PROMPTING A WARMING TREND AND  
LOWER DESERT HIGHS NOW REACHING BETWEEN 100-105 DEGREES.  
EVENTUALLY THE TROUGH WILL SLOWLY DRIFT SOUTHEASTWARD TOWARD OUR  
REGION OVER THE NEXT COUPLE OF DAYS, LOWERING HEIGHTS ALOFT AND  
INDUCING SOME BREEZINESS. BREEZY CONDITIONS ARE LIKELY ACROSS  
SOUTHEAST CALIFORNIA BY THIS EVENING BEFORE SPREADING AREAWIDE ON  
WEDNESDAY. TEMPERATURES WILL ALSO BEGIN TO DROP ACROSS THE WESTERN  
DESERTS STARTING WEDNESDAY AS HIGHS STAY UNDER 100 DEGREES, BUT  
THE PHOENIX METRO IS AGAIN EXPECTED TO TOP OUT BETWEEN 102-105  
DEGREES.  
 
THE INCOMING TROUGH WILL ALSO SHIFT OUR LOW AND MID LEVEL WINDS  
MORE OUT OF THE SOUTH STARTING WEDNESDAY LEADING TO SOME MODEST  
MOISTURE RETURN OUT OF NORTHERN MEXICO. ALTHOUGH THE MOISTURE WILL  
OVERALL BE FAIRLY LIMITED IT SHOULD BE ENOUGH WITH THE HELP OF THE  
WEAK UPPER LEVEL FORCING TO SPARK OFF SOME ISOLATED SHOWERS AND  
MAYBE A WEAK THUNDERSTORM OR TWO ACROSS THE FAR EASTERN ARIZONA  
HIGH TERRAIN WEDNESDAY AFTERNOON/EVENING.  
 

 
   
LONG TERM /THURSDAY THROUGH MONDAY/
 
 
GUIDANCE THEN SHOWS THE PACIFIC TROUGH SHIFTING MORE TO THE EAST  
NORTHEAST THURSDAY IN FRIDAY WITH THE LOW CENTER EVENTUALLY MOVING  
INTO IDAHO AND A WEAK TROUGH AXIS MOVING ACROSS OUR REGION ON  
FRIDAY. GRADUAL HEIGHT FALLS DURING THIS TIME SHOULD CONTINUE TO  
BRING PERIODS OF BREEZINESS ALONG WITH SOME SLIGHT COOLING ACROSS  
THE REGION. SIMILAR TO WEDNESDAY, LOCATIONS ACROSS FAR EASTERN  
ARIZONA MAY SEE SOME LOW END RAIN CHANCES ON THURSDAY INTO  
THURSDAY NIGHT. MOST LOCATIONS ARE NOT LIKELY TO SEE MUCH IF ANY  
RAINFALL GIVEN THE OVERALL LOW MOISTURE CONTENT AIR AND WEAK  
FORCING ASSOCIATED WITH THE PASSING WEATHER SYSTEM. ONCE THE  
TROUGH AXIS PASSES THROUGH LATER ON FRIDAY, MUCH DRIER AIR IS  
EXPECTED TO SPREAD ACROSS THE AREA WITH SURFACE DEW POINTS  
DROPPING INTO THE 30S BY SATURDAY.  
 
TEMPERATURES LATER THIS WEEK ARE EXPECTED TO COOL OFF SLIGHTLY  
WITH MOST LOWER DESERT LOCATIONS TOPPING OUT IN THE MID TO UPPER  
90S STARTING THURSDAY AND LIKELY STAYING THERE THROUGH AT LEAST  
SATURDAY. OVERNIGHT TEMPERATURES WILL ALSO COOL OFF A GOOD AMOUNT  
WITH LOWS DIPPING INTO THE 60S ACROSS THE WESTERN LOWER DESERTS BY  
FRIDAY MORNING AND WELL INTO THE 70S ACROSS THE SOUTH-CENTRAL  
ARIZONA LOWER DESERTS.  
 
THE WEATHER PATTERN IS NOT LIKELY TO CHANGE MUCH GOING INTO NEXT  
WEEK AS A SECOND PACIFIC TROUGH IS LIKELY TO APPROACH THE WEST  
COAST BY SUNDAY BEFORE EVENTUALLY MOVING INLAND EARLY NEXT WEEK.  
THIS SHOULD KEEP OUR TEMPERATURES AT OR JUST BELOW NORMAL AND  
MAINTAIN AN OVERALL DRY WESTERLY FLOW OVER OUR REGION.  
 

 
   
AVIATION
 
UPDATED AT 1115Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION CONCERNS ARE EXPECTED DURING THE TAF PERIOD. WINDS  
WILL FOLLOW FAMILIAR DIURNAL TRENDS, WITH A SLOWER THAN USUAL  
SHIFT TO THE W RESULTING IN A WINDOW OF S'RLY CROSSWINDS AT KPHX.  
OCCASIONAL AFTERNOON BREEZINESS WITH GUSTS 15-20 KTS SHOULD ALSO  
BE ANTICIPATED. OTHER THAN A FEW AFTERNOON CU, SKIES WILL BE  
MOSTLY CLEAR DURING THE MAJORITY OF THE FORECAST WINDOW.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION CONCERNS ARE EXPECTED OVER THE NEXT 24 HOURS.  
WINDS WILL FAVOR A W'RLY COMPONENT AT KIPL, WITH GUSTS THIS  
EVENING UPWARDS OF 25 KTS. AT KBLH, DIURNAL TRENDS (S'RLY SHIFTING  
SW'RLY) WILL PREVAIL, WITH SOME OCCASIONAL GUSTS NEAR 20 KTS THIS  
AFTERNOON. MOSTLY CLEAR SKIES WILL BE OBSERVED THROUGH WEDNESDAY  
MORNING.  
 

 
   
FIRE WEATHER
 
 
THE WEATHER PATTERN OVER THE NEXT SEVERAL DAYS WILL CONTINUE TO  
BRING OVERALL DRY CONDITIONS WITH NEAR NORMAL TEMPERATURES. A  
WEATHER SYSTEM APPROACHING THE REGION FROM THE NORTHWEST WILL  
RESULT IN OCCASIONALLY BREEZY CONDITIONS STARTING TODAY WITH PEAK  
WINDS LIKELY ON WEDNESDAY AS GUSTS REACH TO AROUND 25 MPH AT  
TIMES IN THE AFTERNOON. BY THURSDAY, THERE MAY BE SOME SLIGHT RAIN  
CHANCES ACROSS THE EASTERN ARIZONA HIGH TERRAIN. MINRHS OVER THE  
NEXT FEW DAYS ARE LIKELY TO RANGE FROM 10-15% ACROSS THE WESTERN  
DISTRICTS TO 15-25% ACROSS THE EASTERN DISTRICTS. BY FRIDAY AND  
INTO THE WEEKEND, EVEN DRIER CONDITIONS ARE EXPECTED WITH WINDS  
RETURNING TO A TYPICAL LIGHT AND DIURNAL PATTERN.  
 

 
   
PSR WATCHES/WARNINGS/ADVISORIES
 
 
AZ...NONE.  
CA...WIND ADVISORY FROM 6 PM THIS EVENING TO 6 AM PDT WEDNESDAY FOR  
CAZ562.  
 

 
 

 
 
SHORT TERM...KUHLMAN  
LONG TERM...KUHLMAN  
AVIATION...RW  
FIRE WEATHER...KUHLMAN  
 
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