068
FXUS65 KPSR 260517
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1015 PM MST MON AUG 25 2025
UPDATE
UPDATED AVIATION
KEY MESSAGES
- SHOWERS AND THUNDERSTORMS ARE POSSIBLE AGAIN TUESDAY. LOCALLY
GUSTY WINDS, BLOWING DUST, HEAVY RAINFALL, AND FLOODING WILL BE
POSSIBLE.
- TEMPERATURES COOL THE NEXT COUPLE DAYS, DROPPING TO BELOW NORMAL
LEVELS.
- DRYING CONDITIONS DURING THE LATTER HALF THE WEEK WILL GREATLY
DIMINISH RAIN CHANCES ACROSS THE AREA WITH ACTIVITY LIKELY BECOMING
CONFINED TO HIGH TERRAIN EAST OF PHOENIX BY THE END OF THE WEEK.
SHORT TERM /TODAY THROUGH TUESDAY/
BY LATE THIS EVENING INTO TONIGHT, GUIDANCE GENERALLY AGREES ON A
DIMINISHING THREAT FOR SHOWER AND THUNDERSTORM ACTIVITY. FORECAST
UNCERTAINTY INCREASES FURTHER FOR TUESDAY AS WE ARE LIKELY TO BE
UNDER A SCENARIO WHERE WE HAVE WORKED OVER THE ATMOSPHERE A GOOD
DEAL TODAY LEAVING LESS INSTABILITY FOR TUESDAY. THERE IS ALSO
DIFFERENCES IN THE AMOUNT OF MOISTURE AVAILABLE FOR TUESDAY WITH THE
GEFS INDICATING SOME DRYING ALREADY OCCURRING WHILE THE EPS KEEPS
THE 1.5-1.7" PWATS IN PLACE. NBM POPS ALSO SEEM WAY OUT OF WHACK FOR
TUESDAY PROVIDING HIGHER CHANCES ON TUESDAY VERSUS TODAY. WE HAVE
LOWERED POPS TUESDAY TO MOSTLY SHOW 30-50% CHANCES ACROSS THE LOWER
DESERTS TO 50-70% OVER THE EASTERN ARIZONA HIGHER TERRAIN. TUESDAY
MAY END UP PLAYING OUT WELL FOR THOSE AREAS THAT DO NOT RECEIVE MUCH
CONVECTION TODAY, SPECIFICALLY FROM PHOENIX AND AREAS TO THE EAST OF
PHOENIX. WE ALSO CAN'T RULE OUT A THREAT FOR HEAVY RAINFALL AND
LOCALIZED FLOODING ON TUESDAY FOCUSED MORE OVER THE EASTERN PORTION
OF THE REGION.
TEMPERATURES TODAY WILL DROP FROM WHAT WE SAW OVER THE WEEKEND, BUT
DAYTIME HIGHS TODAY ARE LIKELY TO STILL REACH TO WITHIN A DEGREE OR
TWO OF NORMALS. THE INCREASED MOISTURE AND RAIN COOLED AIR SHOULD
BRING DOWN TEMPERATURES FURTHER FOR TUESDAY WITH HIGHS ANYWHERE FROM
THE MID 90S TO AROUND 100 DEGREES.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
BY WEDNESDAY, THE INFLUENCES OF THE SUBTROPICAL HIGH WILL BE MUCH
LESS AS IT SHIFTS ITS CENTER OVER THE SOUTHERN PLAINS. AT THE SAME
TIME, THE PACIFIC TROUGH WILL NUDGE INTO AT LEAST WESTERN PORTIONS
OF OUR REGION LEADING TO LOWER HEIGHTS AND TURNING OUR FLOW OUT OF
THE SOUTHWEST. THIS WILL BRING IN A GOOD AMOUNT OF DRIER AIR
WEDNESDAY INTO THURSDAY, EVENTUALLY SCOURING OUT MUCH OF OUR LOW
LEVEL MOISTURE BY FRIDAY. HOWEVER, THE LINGERING MOISTURE ON
WEDNESDAY SHOULD STILL BE ENOUGH TO ALLOW FOR SOME ISOLATED SHOWER
AND THUNDERSTORM ACTIVITY LIKELY FOCUSED OVER HIGHER TERRAIN AREAS.
AS THE DRY AIR REALLY SETTLES IN BY THURSDAY, WE SHOULD EXPECT ONLY
VERY MINIMAL RAIN CHANCES ACROSS THE EASTERN ARIZONA HIGH TERRAIN.
THIS WESTERLY FLOW DRY PATTERN IS LIKELY TO CONTINUE THROUGH THE
UPCOMING WEEKEND KEEPING MUCH IF NOT ALL OF OUR AREA DRY.
TEMPERATURES SHOULD CONTINUE TO RUN SLIGHTLY BELOW NORMAL FOR
WEDNESDAY AND THURSDAY BEFORE SOME GRADUAL WARMING PUSHES HIGHS BACK
INTO THE NORMAL RANGE OF 102-105 DEGREES BY FRIDAY. ADDITIONAL
WARMING IS FAVORED OVER THE WEEKEND AS THE SUBTROPICAL HIGH SOMEWHAT
NUDGES BACK INTO OUR REGION. THE NBM SUGGESTS DAYTIME HIGHS WARMING
BACK TO BETWEEN 104-108 DEGREE RANGE FOR THE WEEKEND.
AVIATION
UPDATED AT 0515Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
UNCERTAINTY IN WIND TRENDS OVERNIGHT, THEN CHANCES OF TSRA
DEVELOPMENT TUESDAY AFTERNOON ARE THE MAIN WEATHER ISSUES THIS TAF
PERIOD UNDER PERIODS OF THICKER MID/HIGH CIGS. CONFIDENCE IS
MODERATE THAT N/NW WINDS WILL BECOME EASTERLY BY MIDNIGHT, THOUGH
PERIODS OF VARIABILITY CANNOT BE DISCOUNTED. DIRECTIONS SHOULD SWITCH
BACK TO WESTERLY AROUND OR SLIGHTLY AFTER NOON TUESDAY WITH LIMITED
GUSTINESS. CHANCES FOR TSRA DEVELOPMENT IMPACTING TERMINALS TUESDAY
AFTERNOON IS ONLY 20% GIVEN THE OVERTURNING EXPERIENCED THIS
EVENING. PERHAPS, AN OUTFLOW BOUNDARY COULD CREATE AN ABRUPT WIND
SHIFT, BUT EVEN THAT OUTCOME APPEARS UNLIKELY.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
UNCERTAINTY IN TSRA DEVELOPMENT TUESDAY AFTERNOON IS THE GREATEST
FORECAST ISSUE UNDER PERIODS OF THICK MID/HIGH CIGS. WINDS MAY BE
SOMEWHAT VARIABLE INTO THE OVERNIGHT, HOWEVER SHOULD SETTLE ON A
S/SE TRAJECTORY BY SUNRISE. WHILE AN ISOLD SHRA/TSRA MAY BE POSSIBLE
ANYTIME DURING THE PERIOD, CHANCES ARE LESS THAN 20% WITH MODELING
COMING CLOSEST TO KIPL WITH DECAYING ACTIVITY TUESDAY AFTERNOON.
COVERAGE OF ANY TSRA SHOULD BE FAR LESS THAN TODAY WITH LIMITED
IMPACTS MOSTLY TIED TO WIND SHIFTS.
FIRE WEATHER
ABUNDANT MOISTURE AND PERIODS OF SHOWERS AND THUNDERSTORMS ARE
EXPECTED EARLY THIS WEEK. THE BEST RAINFALL CHANCES TODAY ARE LIKELY
TO BE FOCUSED ACROSS THE WESTERN DISTRICTS BEFORE SHIFTING OVER THE
EASTERN DISTRICTS ON TUESDAY. STRONG GUSTY WINDS, HEAVY RAINFALL AND
LOCALIZED FLOODING WILL BE POSSIBLE, ESPECIALLY TODAY. ELEVATED
HUMIDITIES WILL LEAD TO MINRHS BETWEEN 25-40% TODAY AND TUESDAY
BEFORE GRADUALLY LOWERING BEGINNING WEDNESDAY. TEMPERATURES WILL
DROP INTO THE NORMAL RANGE TODAY AND TO BELOW NORMAL STARTING
TUESDAY. DRYING CONDITIONS LATER THIS WEEK SHOULD MOSTLY END RAIN
CHANCES BY THURSDAY WITH MINRHS DROPPING BACK INTO THE TEENS.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...NONE.
SHORT TERM...WHITTOCK
LONG TERM...KUHLMAN
AVIATION...18
FIRE WEATHER...KUHLMAN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page