787  
FXUS65 KPSR 192323  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
423 PM MST SAT SEP 19 2026  
   
UPDATE  
00Z AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- DRY, TRANQUIL WEATHER CONDITIONS WITH NEAR TO SLIGHTLY ABOVE  
NORMAL TEMPERATURES WILL CONTINUE THROUGH THE FIRST HALF OF NEXT  
WEEK.  
 
- A LOW PRESSURE SYSTEM WITH RETURNING MOISTURE WILL YIELD RENEWED  
RAINFALL CHANCES TO AT LEAST THE HIGH TERRAIN OF NORTHERN AND  
EASTERN ARIZONA DURING THE LATTER HALF OF NEXT WEEK.  
 
 
   
SHORT TERM /TODAY THROUGH MONDAY/  
 
EARLY AFTERNOON WV IMAGERY DEPICTS A SEASONALLY DEEP MIDLEVEL  
CYCLONE OVER THE GREAT BASIN WITH A SOUTHERLY EXTENDED TROUGH AXIS  
SWEEPING INTO EASTERN ARIZONA. WITH THE CENTRAL NEGATIVE HEIGHT  
ANOMALY FILLING AND WEAKENING, LITTLE IN THE WAY OF HEIGHT FALLS OR  
COOLING WILL AFFECT THE SW CONUS, HOWEVER THE RESULTANT FLOW PATTERN  
WILL BECOME INCREASINGLY WESTERLY AS THE REGION PREEMINENTLY  
TRANSITIONS OUT OF MONSOON. LINGERING SHALLOW MOISTURE IN THE FORM  
OF 8-10 G/KG MIXING RATIOS AND TOTAL COLUMN PWATS NEAR 0.75" OVER  
THE EASTERN HALF OF THE CWA WILL BE FURTHER SCOURED AWAY WITH  
VERTICAL MECHANICAL MIXING IN THE DRY WESTERLY FLOW THIS AFTERNOON  
REACHING LEVELS OF 5 G/KG AND 0.50" RESPECTIVELY. WHILE SHALLOW, LOW  
LEVEL MOISTURE WILL OCCASIONALLY SLOSH BACK INTO PARTS OF THE CWA  
OVER THE NEXT 48 HOURS, THE OVERARCHING DRYING ENVIRONMENT WILL  
PRECLUDE DEEP CONVECTION AND RAINFALL CHANCES INTO THE MIDDLE OF  
NEXT WEEK. OTHERWISE, H5 HEIGHTS WILL REMAIN FAIRLY STEADY AROUND  
588DM WITH ONLY MODEST HEIGHT FALLS ENTERING THE REGION MONDAY. AS A  
RESULT, FORECAST CONFIDENCE IS EXCELLENT THAT TEMPERATURES WILL  
HOVER WITHIN A FEW DEGREES OF THE SEASONAL NORMAL YIELDING ONLY  
MINOR HEATRISK.  
 
 
   
LONG TERM /TUESDAY THROUGH FRIDAY/  
 
ON TUESDAY, AN UPPER LOW WILL SLOWLY WEAKEN AS IT MOVES NORTHEAST  
INTO NV/UT BEFORE GETTING SWEPT UP INTO THE LARGE SCALE FLOW ON  
WEDNESDAY MOVING INTO THE NORTHERN PLAINS. AT THE SAME TIME, A WEAK  
RIDGE OVER TX AND WILL START TO STRENGTHEN ON RESULTING IN  
SOUTHWESTERLY FLOW OVER OUR AREA. WITH MOISTURE RETURN AND SOME  
UPPER LEVEL FORCING FROM THE AFOREMENTIONED LOW, RAIN CHANCES WILL  
RETURN TO THE HIGHER TERRAIN AREAS IN NORTHERN AND EASTERN ARIZONA.  
WEAK LARGE SCALE TROUGHING WILL REMAIN ACROSS THE EASTERN  
PACIFIC/WEST COAST THROUGH THE END OF NEXT WEEK, BATTLING THE RIDGE  
OF HIGH PRESSURE OVER TX. BY THE END OF THE WEEK, THE RIDGE WILL  
TRY TO RETROGRADE INTO NM/AZ. ADDITIONALLY, ENSEMBLE MEMBERS BRING A  
SURGE OF MOISTURE INTO OUR AREA FROM THE SE, PUSHING PWATS BACK INTO  
A 1.0-1.3" RANGE. AS A RESULT, NBM/WPC POPS FOR THE END OF NEXT WEEK  
REFLECT A 30-50% CHANCE OF SHOWERS AND STORMS ACROSS THE HIGHER  
TERRAIN IN SOUTHERN GILA COUNTY, AND AROUND 10-20% ACROSS THE LOWER  
DESERTS OF SOUTH-CENTRAL ARIZONA.  
 
TEMPERATURES NEXT WEEK WILL REMAIN LARGELY UNCHANGED IN THE UPPER  
90S TO LOW 100S ACROSS THE LOWER DESERTS, AND IN THE UPPER 80S TO  
MID 90S ACROSS THE HIGHER TERRAIN. MORNING LOWS WILL GENERALLY BE  
IN THE 70S TO TO LOW 80S ACROSS THE LOWER DESERTS, AND IN THE 60S  
ACROSS THE HIGHER TERRAIN AREAS. MORNING LOWS SHOULD START TO CREEP  
UP BY THE END OF NEXT WEEK (MORE MORNING LOWS IN THE LOW 80S ACROSS  
THE LOWER DESERTS). AS A RESULT, WIDESPREAD MINOR HEATRISK WILL  
CONTINUE THROUGH THE BEGINNING OF NEXT WEEK WITH MODERATE HEATRISK  
RETURNING TO THE LOWER DESERTS FOR THE LATTER HALF OF NEXT WEEK AS  
THE MORNING LOWS CREEP UP AND DAILY NORMALS DECREASE.  
 
 
   
AVIATION  
UPDATED AT 2320Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION WEATHER CONCERNS WILL EXIST THROUGH THE TAF PERIOD  
UNDER MOSTLY CLEAR SKIES TONIGHT, FOLLOWED BY INCREASING HIGH  
CLOUDS ON SUNDAY. WINDS WILL FOLLOW TYPICAL DIURNAL PATTERNS WITH  
SPEEDS REMAINING AOB 8 KTS. A 3-4 HR PERIOD OF LIGHT SOUTHERLY  
CROSS-RUNWAY WINDS IS LIKELY AGAIN AT KPHX, EARLY SUNDAY AFTERNOON  
BEFORE SHIFTING OUT OF THE SOUTHWEST.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION WEATHER CONCERNS WILL EXIST AT THE SE CALIFORNIA  
TERMINALS THROUGH SUNDAY. CLEAR SKIES WILL PREVAIL THIS EVENING,  
FOLLOWED BY INCREASING HIGH CLOUDS OVERNIGHT INTO SUNDAY. WINDS  
WILL FOLLOW DIURNAL TRENDS REMAINING GENERALLY BELOW 10 KTS AT  
BOTH TERMINALS. HOWEVER, A FEW GUSTS INTO THE MID TEENS WILL BE  
POSSIBLE AT KIPL THIS EVENING. THERE WILL ALSO BE EXTENDED PERIODS  
OF CALM AND VRB CONDITIONS AT BOTH TERMINALS EARLY SUNDAY MORNING.  
 
 
   
FIRE WEATHER  
 
OVERALL THERE ARE NO FIRE WEATHER CONCERNS THROUGH THE NEXT WEEK.  
CONDITIONS WILL CONTINUE TO DRY OUT TODAY WITH NO CHANCES FOR RAIN  
CONTINUING THROUGH MONDAY. SLIGHT CHANCES FOR SHOWERS AND STORMS  
RETURN TO THE HIGHER TERRAIN AREAS OF SOUTHERN GILA COUNTY BEGINNING  
ON TUESDAY. MINRHS WILL BE AROUND 10-25% TODAY AND TOMORROW BEFORE  
INCREASING TO AROUND 15-30% FOR THE FIRST HALF OF NEXT WEEK.  
OVERNIGHT RECOVERIES WILL RANGE FROM FAIR TO GOOD ACROSS THE REGION  
THROUGH THE MIDDLE OF NEXT WEEK. BESIDES A POTENTIAL INCREASE IN  
BREEZINESS EARLY NEXT WEEK WITH A WEATHER SYSTEM, WINDS WILL MOSTLY  
FOLLOW TYPICAL DIURNAL PATTERNS WITH MODEST AFTERNOON  
UPSLOPE/UPVALLEY GUSTINESS (15-25 MPH).  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
SHORT TERM...18  
LONG TERM...BERISLAVICH  
AVIATION...SALERNO  
FIRE WEATHER...BERISLAVICH/BENEDICT  
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