024  
FXUS65 KPSR 222325  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
425 PM MST THU OCT 22 2026  
   
UPDATE  
00Z AVIATION DISCUSSION.  
 
 
   
KEY MESSAGES  
 
- THUNDERSTORMS CAPABLE OF SEVERE WEATHER AND FLOODING WILL EXIT  
THROUGH EASTERN ARIZONA THIS EVENING WITH DRIER AIR SURGING INTO THE  
REGION.  
 
- MORE BENIGN WEATHER CONDITIONS WILL FILTER INTO THE AREA  
FRIDAY AND THROUGH THE WEEKEND WITH ONLY A FEW LINGERING SHOWERS  
OVER MOUNTAIN LOCATIONS IN ARIZONA.  
 
- BELOW NORMAL TEMPERATURES THROUGH EARLY NEXT WEEK WILL WARM CLOSER  
TO THE SEASONAL AVERAGE BY THE MIDDLE OF NEXT WEEK.  
 
 
   
SHORT TERM /TODAY THROUGH SATURDAY/  
 
DEEP NEGATIVE HEIGHT ANOMALIES WERE FINALLY MOVING INLAND ACROSS  
SOUTHERN CALIFORNIA WITH A NOTABLE TROUGH AXIS ROTATING INTO SE  
CALIFORNIA/SW ARIZONA. A STRONG JET CORE HAS SHIFTED TO THE  
EASTERN SIDE OF THE LARGER CIRCULATION ENSURING FURTHER LIFTING OF  
COLD CORE ALOFT TOWARDS SOUTHERN UTAH WHILE ALLOWING DEEP DOWNSTREAM  
MERIDIONAL FLOW TO VEER MORE W/SW. WHILE MUCH OF THE EASTERN CWA  
REMAINS IN THE RIGHT REAR JET QUADRANT FAVORABLE FOR SYNOPTIC  
ASCENT THIS AFTERNOON, THE PROPAGATION OF THE AFOREMENTIONED TROUGH  
AXIS WILL PLACE THE REGION UNDER GROWING SUBSIDENCE AFTER THIS  
EVENING. CONCURRENTLY, A PLUME OF AMPLE MOISTURE REMAINS SITUATED  
FROM THE PHOENIX METRO EASTWARD WITH PWATS AROUND 1.25" AND LOW  
LEVEL MIXING RATIOS 10-12 G/KG YIELDING MLCAPE 1000-1500 J/KG.  
KINEMATIC FIELDS CONTINUE TO SUPPORT ORGANIZED SUPERCELL STRUCTURE  
GIVEN 0-6KM SHEAR ABOVE 50KT WHILE HODOGRAPHS INCREASINGLY BECOMING  
STRAIGHT-LINED WOULD POINT TOWARDS SPLITTING CELLS, AND SIMILAR TO  
YESTERDAY PREFERRING LEFT MOVERS PRODUCING VERY LARGE HAIL  
(SUFFICIENT 400-600 J/KG CAPE WITHIN THE -10C TO -30C HAIL GROWTH  
REGION AS WELL). WHILE A TORNADO THREAT WILL PERSIST IN GILA COUNTY  
WITH A WATCH THROUGH 8 PM, WEAKENING 0-1KM SHEAR VECTORS AND HIGHER  
LCL'S MAY KEEP THE GREATER THREAT TO THE EAST AND NORTH OF GILA  
COUNTY.  
 
RECENT OBJECTIVE ANALYSIS DEPICTS THE WEDGE OF DRY AIR BEHIND A  
THETA-E BOUNDARY AND IN ASSOCIATION WITH THE DEEPER VEERED WINDS  
ALREADY BISECTING THE PHOENIX METRO EARLY THIS AFTERNOON. THIS  
BOUNDARY WILL CONTINUE TO PROGRESS EASTWARD THROUGH THE EVENING  
ERODING INSTABILITY AND ELIMINATING THE CONVECTIVE THREAT BEYOND  
MID EVENING. IT'S NOT OUT OF THE QUESTION A LINGERING SHOWER COULD  
AFFECT EASTERN ARIZONA HIGH TERRAIN TONIGHT, HOWEVER HREF AND REFS  
OUTPUT OFFER ONLY MINIMAL SUPPORT FOR THIS OUTCOME. ON FRIDAY, A  
SECONDARY VORTICITY CENTER EMANATING OVER THE EAST PACIFIC WILL DIVE  
INTO THE MEAN TROUGH POSITION ACROSS THE SW CONUS CREATING A QUASI-  
CUTOFF LOW THAT WILL PERSIST THROUGH SATURDAY. WITH BETTER MOISTURE  
ALREADY SCOURED FROM THE AREA, ONLY MOUNTAIN LOCATION MAY BE CAPABLE  
OF SQUEEZING OUT A FEW DIURNAL SHOWERS UNDER THE COLD CORE SATURDAY  
WITH LOWER ELEVATIONS REMAINING DRY. THIS SYSTEM WILL ENSURE H5  
HEIGHTS REMAIN SEQUESTERED UNDER 572DM THROUGH SATURDAY WITH  
EXCELLENT FORECAST CONFIDENCE OF TEMPERATURES SOLIDLY 10F BELOW  
NORMAL.  
 
 
   
LONG TERM /SUNDAY THROUGH THURSDAY/  
 
MODEL GUIDANCE SUGGESTS THE AFOREMENTIONED CUTOFF SHOULD REMAIN OVER  
THE REGION THROUGH THE ENTIRE WEEKEND, BUT CONTINUING TO WEAKEN  
ALLOWING THE AIRMASS TO SLOWLY WARM OVER TIME. NBM FORECAST HIGHS  
SUNDAY SHOW READINGS REBOUNDING INTO THE LOWER 80S OVER THE WESTERN  
LOWER DESERTS TO NEAR 80 DEGREES IN THE PHOENIX AREA. BY MONDAY, THE  
TROUGH IS LIKELY TO FINALLY PUSH EAST OF THE REGION WITH MODEST  
UPPER LEVEL RIDGING PREVAILING OVER THE DESERT SOUTHWEST. THE  
INCREASED HEIGHTS AND CONTINUED DRY CONDITIONS SHOULD PUSH DAYTIME  
HIGHS BACK INTO THE NORMAL RANGE (MID 80S) GOING INTO THE MIDDLE OF  
NEXT WEEK.  
 
 
   
AVIATION  
UPDATED AT 2325Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO AVIATION CONCERNS ARE EXPECTED THROUGH THE FORECAST PERIOD  
UNDER GRADUALLY CLEARING SKIES. WINDS WILL REMAIN SW TO W THROUGH  
THIS EVENING WITH OCCASIONAL GUSTS UP AROUND 20 KT EXPECTED AT ALL  
TERMINALS THROUGH SUNSET. THEREAFTER, WINDS WILL RELAX AND SWITCH  
BACK OUT OF THE E-SE LATE TONIGHT. FEW TO SCT CLOUDS AROUND 6-7  
KFT WILL CONTINUE TO DISSIPATE AS DRY AIR MOVES INTO THE AREA.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR AVIATION WEATHER CONCERNS ARE ANTICIPATED THROUGH THE  
FORECAST PERIOD. WINDS WILL FAVOR A SW-W COMPONENT AT KBLH AND  
W-NW AT KIPL. INTERMITTENT GUSTS UP TO 20-25 KTS WILL BE COMMON  
OVER THE NEXT FEW HOURS WITH A FEW GUSTS EXCEEDING 30 KTS POSSIBLE  
AT KIPL. OTHERWISE, GUSTS SHOULD DIMINISH BY MIDNIGHT AND SPEEDS  
WILL FALL TO 10 KTS OR LESS. FEW TO SCT CLOUDS, MOSTLY AOA 7 KFT,  
WILL CONTINUE INTO THE EVENING BEFORE BECOMING CLEAR OVERNIGHT.  
 
 
   
FIRE WEATHER  
 
STRONG TO SEVERE THUNDERSTORMS WITH HEAVY RAINFALL WILL REMAIN  
POSSIBLE OVER EASTERN DISTRICTS THROUGH THIS AFTERNOON BEFORE RAPID  
DRYING SPREADS THROUGH THE AREA THIS EVENING AND TONIGHT. THE  
HEAVIEST RAINFALL WILL BE FOCUSED MORE ACROSS HIGHER TERRAIN AREAS  
NORTH AND EAST OF PHOENIX. MINRHS TODAY WILL AGAIN BE IN A 30-60%  
RANGE BEFORE DROPPING MORE INTO A 25-40% RANGE FOR FRIDAY AND  
SATURDAY AS COOLER AIR SETTLES INTO THE REGION. GUSTY WEST WINDS  
UPWARDS OF 25-30 MPH WILL BE POSSIBLE ACROSS THE WESTERN DISTRICTS  
THROUGH THIS EVENING WITH WINDS BECOMING LIGHT STARTING TONIGHT.  
OVERALL QUIET WEATHER CONDITIONS ARE FORECAST FOR THIS WEEKEND INTO  
NEXT WEEK WITH FAIRLY STABLE HUMIDITIES AND TEMPERATURES REBOUNDING  
BACK INTO THE NORMAL RANGE EARLY NEXT WEEK.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...FLOOD WATCH UNTIL 11 PM MST THIS EVENING FOR AZZ545-547-552-  
556>558-560>563.  
 
FLOOD WATCH UNTIL 5 PM MST THIS AFTERNOON FOR AZZ541-549-555.  
 
CA...NONE.  
 
 
 
 
SHORT TERM...18  
LONG TERM...18/KUHLMAN  
AVIATION...SALERNO  
FIRE WEATHER...KUHLMAN  
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