031  
FXUS65 KPSR 030515  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1015 PM MST WED JUL 2 2025  
   
KEY MESSAGES  
 
- CHANCES FOR ISOLATED TO SCATTERED THUNDERSTORMS WILL EXIST THROUGH  
THIS EVENING ACROSS SOUTH-CENTRAL ARIZONA WITH THE POTENTIAL FOR  
STRONG GUSTY WINDS, BLOWING DUST, AND LOCALIZED HEAVY RAINFALL.  
 
- AFTER LINGERING CHANCES FOR A ISOLATED THUNDERSTORMS THURSDAY,  
DRIER CONDITIONS WILL END ANY RAIN CHANCES BEGINNING THURSDAY NIGHT.  
 
- NEAR NORMAL TEMPERATURES WILL BE COMMON THROUGH SATURDAY BEFORE  
A WARMING TREND BEGINS EARLY NEXT WEEK.  
 
 
   
SHORT TERM/TODAY THROUGH THURSDAY/  
 
THE CURRENT SYNOPTIC SET UP SHOWS AN UNSEASONABLY STRONG PACIFIC LOW  
CENTERED NEAR LOS ANGELES AND THE SUB-TROPICAL HIGH SLOWLY  
RETREATING TO THE NORTHEAST INTO COLORADO. SOUTHEASTERLY FLOW SINCE  
YESTERDAY CONTINUES TO FEED MODESTLY MOIST AIR INTO ARIZONA TO AS  
FAR NORTH AS SOUTHERN NEVADA WITH PWATS NOW UP TO BETWEEN 1.0-1.2"  
OVER THE SOUTHERN HALF OF ARIZONA. THIS MOIST FETCH IS EXPECTED TO  
LAST INTO THIS AFTERNOON WITH PWATS LIKELY PEAKING BETWEEN 1.2-1.4"  
AND LOW LEVEL MIXING RATIOS MOSTLY BETWEEN 8-10 G/KG. THIS AMOUNT OF  
MOISTURE WOULD NORMALLY NOT BE SUFFICIENT FOR A GOOD AMOUNT OF  
MONSOON STORM ACTIVITY, BUT WITH THE HELP OF THE INCOMING  
(WEAKENING) PACIFIC LOW, THE MOISTURE SHOULD END UP BEING SUFFICIENT.  
 
FOR THURSDAY, MODEL GUIDANCE CONTINUES TO SHOW THE WEAKENING PACIFIC  
TROUGH TRACKING NORTHEASTWARD THROUGH NORTHERN ARIZONA WITH DRY AIR  
SURGING EASTWARD ACROSS THE STATE. FOR THE MOST PART, GUIDANCE SHOWS  
ONLY 10-15% CHANCES FOR ANY ADDITIONAL SHOWERS OR THUNDERSTORMS  
ACROSS THE SOUTH-CENTRAL ARIZONA LOWER DESERTS THURSDAY MORNING AND  
EARLY AFTERNOON TO AS HIGH AS 30-35% OVER GILA CO. GIVEN THE DRYING,  
ANY ACTIVITY WILL LIKELY BE ON THE WEAKER SIDE WITH POTENTIAL  
RAINFALL AMOUNTS MUCH LESS THAN TODAY. TEMPERATURES FOR TODAY AND  
THURSDAY WILL BE NOTICEABLY LESS HOT THAN THE PAST FEW DAYS WITH  
HIGHS AT OR JUST BELOW NORMAL.  
 
 
   
LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/  
 
AS THE WEATHER PATTERN SETTLES BACK INTO WESTERLY DRY FLOW OVER THE  
MAJORITY OF THE REGION, RAIN CHANCES ARE EXPECTED TO COME TO AN END  
BY THURSDAY NIGHT. PWATS ARE FORECAST TO DROP DOWN TO BETWEEN 0.8-  
1.0" STARTING FRIDAY AND LIKELY LAST THERE THROUGH THE REST OF THE  
4TH OF JULY WEEKEND. NEAR NORMAL TEMPERATURES ARE LIKELY TO CONTINUE  
INTO SATURDAY WITH OVERNIGHT LOWS FOR RURAL DESERT AREAS EASILY  
FALLING INTO THE 70S AS MOISTURE DECREASES, BUT LOWS WITHIN PHOENIX  
AREA STILL LIKELY TO STAY JUST ABOVE 80 DEGREES.  
 
MODEL UNCERTAINTY INCREASES CONSIDERABLY NEXT WEEK AS THE GEFS SHOWS  
AN INCREASE IN MOISTURE BY AROUND TUESDAY, WHEREAS THE EPS KEEPS THE  
MOISTURE WELL TO THE SOUTH. BOTH GENERALLY AGREE THE SUB-TROPICAL  
RIDGE WILL AGAIN SET UP OVER OUR REGION BY EARLY NEXT WEEK, FIRST  
CENTERED JUST TO OUR EAST BEFORE GRADUALLY SHIFTING WESTWARD THROUGH  
OUR REGION DURING THE MIDDLE OF NEXT WEEK. HEIGHTS ARE ALSO FAVORED  
TO RISE DURING THIS TIME AS THE RIDGE STRENGTHENS, PUSHING H5  
HEIGHTS FROM 590-592DM STARTING SUNDAY TO AS HIGH AS 595-597DM BY  
THE MIDDLE OF NEXT WEEK. THE RECENT SHIFT FOR A STRONGER RIDGE  
SETTING UP OVER OUR REGION HAS ABRUPTLY TURNED CONDITIONS NOTICEABLY  
HOTTER FOR NEXT WEEK WITH NBM HIGHS NOW MOSTLY BETWEEN 110-113  
DEGREES BY TUESDAY. IF THIS NEW SCENARIO OF A STRONGER RIDGE COMES  
TO FRUITION AND MOISTURE STAYS OUT OF OUR AREA, EXPECT FORECAST  
TEMPERATURES TO TREND EVEN HOTTER THAN THE LATEST FORECAST. IF THE  
GEFS IS MORE CORRECT SHOWING BETTER MOISTURE, THAN WE MAY SEE AT  
LEAST A RETURN OF MONSOON ACTIVITY FOR HIGHER TERRAIN AREAS.  
HOWEVER, FOR NOW IT DOES NOT LOOK VERY PROMISING FOR ANY DECENT  
MONSOON STORMS THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK.  
 
 
   
AVIATION  
UPDATED AT 0515Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:  
UNCERTAINTY REGARDING WINDS OVERNIGHT, THEN THE POTENTIAL FOR ISOLD  
SHRA/TSRA THURSDAY AFTERNOON WILL BE THE PRIMARY WEATHER ISSUES THIS  
TAF PERIOD. AS VERY LIGHT -RA AND 10K FT CIGS CLEAR THE TERMINALS  
LATE THIS EVENING, WINDS WILL BRIEFLY BECOME HIGHLY VARIABLE BEFORE  
SETTLING ON A E/SE COMPONENT THOUGH CONFIDENCE IN TIMING AND EXACT  
DIRECTIONS IS ONLY MODERATE. CONFIDENCE IS HIGHER THAT THE WIND  
SHIFT BACK TO W/SW WILL OCCUR BY LATE THURSDAY AFTERNOON UNDER SCT  
MIDLEVEL CLOUD DECKS. WHILE A FEW ISOLD SHRA/TSRA COULD POP AROUND  
THE AIRSPACE LATE AFTERNOON, PROBABILITIES ARE FAR TOO LOW TO  
INCLUDE IN TAFS WITH WEST WINDS LIKELY PERSISTING WELL INTO THURSDAY  
NIGHT.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO MAJOR WEATHER CONCERNS WILL EXIST THROUGH THURSDAY NIGHT UNDER  
MOSTLY CLEAR SKIES. WIND DIRECTIONS WILL GENERALLY VARY BETWEEN SE  
DURING THE MORNING/EARLY AFTERNOON AND SW DURING THE EVENING/EARLY  
OVERNIGHT PERIOD. A FEW GUSTS AROUND 20KT WILL BE COMMON, ESPECIALLY  
AT KBLH.  
 
 
   
FIRE WEATHER  
 
INCREASED MOISTURE ALONG WITH AN INCOMING WEATHER SYSTEM IS EXPECTED  
TO BRING AN ACTIVE DAY TODAY ACROSS THE EASTERN DISTRICTS. SHOWER  
AND THUNDERSTORM CHANCES TODAY ACROSS THE EASTERN DISTRICTS ARE  
BETWEEN 30-50% WITH GUSTY ERRATIC WINDS LIKELY TO OCCUR WITH THE  
THUNDERSTORM ACTIVITY. HUMIDITIES WILL CONTINUE TO IMPROVE TODAY  
WITH MINRHS OF 20-30% FOR THE EASTERN DISTRICTS TO 15-20% FOR THE  
WESTERN DISTRICTS. A DRYING TREND WILL BEGIN THURSDAY WITH MUCH MORE  
ISOLATED CHANCES FOR SHOWERS AND THUNDERSTORMS FOR THE EASTERN  
DISTRICTS. MINRHS THURSDAY WILL MAINLY DIP TO BETWEEN 15-20%. EVEN  
DRIER AIR WILL FILTER INTO THE REGION BY THE WEEKEND WITH MINRHS  
FALLING TO 10-15% BY SUNDAY. TEMPERATURES WILL RUN NEAR NORMAL  
THROUGH SATURDAY BEFORE HEATING UP AGAIN INTO NEXT WEEK.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
 
SHORT TERM/LONG TERM...KUHLMAN/95  
AVIATION...18  
FIRE WEATHER...KUHLMAN  
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