733  
FXUS65 KPSR 031120  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
420 AM MST WED JUN 3 2026  
   
UPDATE  
 
UPDATED AVIATION  
 
 
   
KEY MESSAGES  
 
- SLIGHTLY ABOVE NORMAL TEMPERATURES WITH AREAS OF MODERATE HEATRISK  
WILL PREVAIL THROUGHOUT THE WEEK BEFORE RETREATING CLOSER TO NORMAL  
OVER THE WEEKEND.  
 
- OTHER THAN A SLIGHT CHANCE OF A SHOWER OR THUNDERSTORM IN EASTERN  
ARIZONA DURING THE NEXT FEW AFTERNOONS, DRY CONDITIONS UNDER MOSTLY  
SUNNY SKIES WILL PREVAIL THROUGH THE WEEKEND.  
 
- LOCALLY BREEZY CONDITIONS WILL DEVELOP LATE IN THE WEEK AND THIS  
WEEKEND, PARTICULARLY ACROSS THE LOWER COLORADO RIVER VALLEY AND  
HIGHER TERRAIN COMMUNITIES.  
 
 
   
SHORT TERM /TODAY THROUGH FRIDAY/  
 
CURRENT OBJECTIVE ANALYSIS REVEALS A FAIRLY COMPLEX PATTERN OVER  
CONUS WITH AN OMEGA BLOCK BEGINNING TO BREAK DOWN OVER THE NORTHERN  
TIER OF THE COUNTY, WHILE A WEAK PACIFIC LOW MEANDERS CLOSE TO THE  
BAJA PENINSULA. THE LATTER OF THESE FEATURES WILL CONTINUE ON  
SOUTHEASTWARD PROGRESSION, EVENTUALLY SETTLING OVER CHIHUAHUA,  
MEXICO BY THE END OF THE WORKWEEK. DURING THIS PROGRESSION, OUR  
REGIONAL HEIGHT FIELD WILL NOT CHANGE MUCH, HOVERING AROUND 586-  
587DAM THROUGH FRIDAY, SLIGHTLY ABOVE NORMAL FOR THE START OF JUNE.  
THIS WILL TRANSLATE TO SURFACE TEMPERATURES ALSO RUNNING A FEW  
DEGREES (4-6F) ABOVE NORMAL WITH LOWER DESERT HIGHS RUNNING BETWEEN  
103-109 DEGREES THROUGH FRIDAY. ALTHOUGH NOT COMPLETELY ABNORMAL,  
THESE TEMPERATURES WILL STILL RESULT IN WIDESPREAD MODERATE  
HEATRISK, POSING A RISK TO THOSE SENSITIVE TO THE HEAT AND OTHERS  
WHO MAY NOT HAVE WAYS OF SUFFICIENTLY COOLING OR HYDRATING  
THEMSELVES.  
 
THE ONLY NOTICEABLE DEVIATION FROM HOT AND CALM CONDITIONS THROUGH  
THE NEXT FEW DAYS WILL COME IN THE FORM OF SOME VERY ISOLATED  
SHOWERS AND THUNDERSTORMS OVER FAR EASTERN GILA COUNTY THIS  
AFTERNOON AND AGAIN THURSDAY, AND SOME BREEZY CONDITIONS DEVELOPING  
AROUND THE LOWER COLORADO RIVER VALLEY AND HIGHER TERRAIN AREAS.  
TOWARD THE END OF THE WEEK. THE SLIGHTLY INCREASED RAINFALL POTENTIAL  
IS THE RESULT OF SOME MODEST MOISTURE ADVECTION WORKING ITS WAY  
WESTWARD FROM CONVECTIVE ACTIVITY THAT SPAWNED OVER CENTRAL AND  
EASTERN NEW MEXICO. PWAT ANOMALIES MAY ACTUALLY PUSH NORTH OF 150-  
200% AS FAR WEST AS EASTERN MARICOPA AND PINAL COUNTIES, BUT GIVEN  
THAT JUNE IS CLIMATOLOGICALLY OUR DRIEST MONTH, IT DOES NOT TAKE  
MUCH MOISTURE TO INFLATE THOSE VALUES. THE BEST MOISTURE WILL BE  
FOCUSED OVER THE WHITE MOUNTAINS, ALONG WITH OTHER ENHANCED TERRAIN  
FEATURES IN GRAHAM AND GREENLEE COUNTIES. HOWEVER, IT IS NOT OUT OF  
THE QUESTION THAT CONVECTION OVER THESE AREA PUSHES AN OUTFLOW  
TOWARD OUR AREA OF GILA COUNTY AND SPARKS SOME ISOLATED SHOWERS OR  
THUNDERSTORMS, THOUGH CHANCES ARE SLIM AROUND 10-20%. AS FOR THE  
WINDS, MODELS HAVE AN EASTERN PACIFIC RIDGE INTERACTING WITH THE  
PREVIOUSLY MENTIONED NORTHERN MEXICO LOW, SUBTLY ENHANCING OUR  
REGIONAL PRESSURE GRADIENT. BY THURSDAY, GUSTS 20-25 MPH WILL BE  
MOST COMMON FOR AREAS MENTIONED ABOVE, INCREASE TO 25-30 MPH BY  
FRIDAY. WITH RH VALUES RUNNING AROUND 10% AND BELOW, EVEN THIS  
MARGINAL BREEZINESS WILL RESULT IN ELEVATED FIRE DANGER.  
 
 
   
LONG TERM /SATURDAY THROUGH TUESDAY/  
 
AS WE HEAD INTO THE WEEKEND, ENSEMBLES POINT TOWARDS ANOTHER TROUGH  
MOVING OVER WESTERN PORTIONS OF THE CONUS, WHICH WILL EVENTUALLY  
BECOME MORE AMPLIFIED AND STRETCH FROM BRITISH COLUMBIA DOWN THE  
CALIFORNIA COAST. HOWEVER, UNCERTAINTY REMAINS REGARDING THE  
STRENGTH AND POSITIONS OF THIS POTENTIAL DISTURBANCE. THE INCREASING  
TEMPERATURE SPREAD THROUGH THE WEEKEND AND INTO THE START OF NEXT  
WEEK BETWEEN THE NBM 25TH AND 75TH PERCENTILE REFLECTS THIS  
UNCERTAINTY. NONETHELESS, EVEN WITH THE COOLER AIR ASSOCIATED WITH  
THIS POTENTIAL SYSTEM, IT APPEARS WIDESPREAD TRIPLE DIGITS ARE HERE  
TO STAY. REGARDLESS OF WHICH ENSEMBLE SOLUTION COMES TO FRUITION,  
THE CONTINUATION OF BREEZY, TO PERHAPS LOCALLY WINDY CONDITIONS  
APPEARS LIKELY. THE MAIN QUESTION WILL BE HOW STRONG GUSTS MAY  
BECOME, WHICH WILL BE DEPENDENT ON HOW TIGHT THE REGIONAL PRESSURE  
GRADIENT BECOMES. WITH LITTLE MOISTURE FLUX, ANY BREEZINESS WILL  
KEEP THE FIRE WEATHER RISK ELEVATED AT LEAST THROUGH SUNDAY.  
 
FORECAST CONFIDENCE DOES NOT IMPROVE FOR THE START OF NEXT WEEK AS  
MODEL CLUSTERS SHOW A WIDE VARIETY OF OUTCOMES, WITH SOME SHOWING  
CONTINUED TROUGHING, WHILE OTHERS FAVOR THE RETURN OF HIGH PRESSURE.  
THE RETURN OF RIDGING ACROSS THE WESTERN CONUS APPEAR TO BE MOST  
LIKELY OUTCOME AT THIS TIME, BUT HOW AMPLIFIED THIS FEATURE BECOMES,  
ITS PLACEMENT, AND IF WE REMAIN UNDER SOME INFLUENCE OF A LINGERING  
AREA OF LOW PRESSURE REMAINS UNCERTAIN AT THIS TIME. ONE THING THAT  
DOES APPEAR CERTAIN THOUGH, OTHER THAN OUR HIGH TERRAIN RAIN CHANCES  
TODAY AND THURSDAY, DRY CONDITIONS ARE LIKELY TO PREVAIL OVER THE  
NEXT WEEK AT LEAST FOR MOST OF THE REGION.  
 
 
   
AVIATION  
UPDATED AT 1120Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT; AND  
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
 
NO SIGNIFICANT WEATHER ISSUES WILL EXIST THROUGH THURSDAY MORNING  
UNDER PASSING CIRRUS DECKS AND A FEW AFTERNOON CU/CB DEVELOPING OVER  
MOUNTAINS EAST OF PHOENIX. CONFIDENCE IS VERY GOOD THAT TRENDS IN  
WIND SPEEDS AND TIMING OF DIRECTIONAL SHIFTS WILL BE VERY SIMILAR TO  
THE PAST 24 HOURS. HOWEVER, THE LATE EVENING/OVERNIGHT SHIFT BACK TO  
AN EASTERLY DIRECTION AROUND THE PHOENIX METRO MAY OCCUR A FEW HOURS  
EARLIER THAN THE PAST COUPLE DAYS DUE TO DECAYING OUTFLOW DESCENDING  
INTO THE VALLEY FROM STORMS OVER MOUNTAINS.  
 
 
   
FIRE WEATHER  
 
THE THREAT FOR A ISOLATED DRY THUNDERSTORMS OVER SOUTHERN GILA  
COUNTY TODAY AND THURSDAY IS THE MAIN FIRE WEATHER HAZARD OVER THE  
NEXT FEW DAYS. WINDS WILL FOLLOW TYPICAL DIURNAL TENDENCIES WITH  
TYPICAL AFTERNOON UPSLOPE BREEZINESS THE NEXT COUPLE OF AFTERNOONS.  
GUSTS BEGIN TO PICK UP FRIDAY AND INTO THE WEEKEND, MAINLY ACROSS  
THE LOWER COLORADO RIVER VALLEY AND HIGH TERRAIN AREAS OF THE  
EASTERN DISTRICTS. WITH DAILY MINRHS HOVERING CLOSE TO 5-10%, EVEN  
MARGINAL BREEZES WILL RESULT IN PERIODS OF ELEVATED FIRE WEATHER  
CONDITIONS. ISOLATED INSTANCES OF NEAR CRITICAL TO CRITICAL  
CONDITIONS CANNOT BE RULED OUT. OVERNIGHT RECOVERY WILL OFFER VERY  
LITTLE IN TERMS OF RELIEF AS MAXRHS RUN BETWEEN ONLY 15-45% FOR MOST  
AREAS. BREEZY, TO LOCALLY WINDY, CONDITIONS ARE LIKELY TO CONTINUE  
INTO THE WEEKEND, POTENTIALLY LINGERING INTO THE START OF NEXT WEEK,  
RESULTING IN A PROLONGED PERIOD OF DAILY OCCURRENCES OF ELEVATED TO  
NEAR CRITICAL FIRE WEATHER CONDITIONS STARTING ON FRIDAY.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
 
SHORT TERM...RW  
LONG TERM...RW  
AVIATION...18  
FIRE WEATHER...RW  
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