439
FXUS65 KPSR 091730
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
1030 AM MST THU JUL 9 2026
UPDATE
18Z AVIATION DISCUSSION
KEY MESSAGES
- HOT TEMPERATURES WILL CONTINUE THROUGH THE END OF THE WORK WEEK
RESULTING IN AREAS OF MAJOR HEATRISK. EXTREME HEAT WARNINGS
REMAIN IN EFFECT THROUGH THIS EVENING ACROSS ALL OF THE LOWER
DESERT LOCATIONS, WITH THE WARNING EXTENDED THROUGH FRIDAY
ACROSS WESTERN IMPERIAL COUNTY, THE LOWER COLORADO RIVER VALLEY,
AND THE PHOENIX METRO.
- THE CHANCES FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE
HIGHER TERRAIN AREAS OF THE EASTERN AND SOUTHEASTERN THIRD OF
ARIZONA THROUGH FRIDAY.
- AS DEEPER MOISTURE MOVES IN, THE CHANCES FOR MORE WIDESPREAD
THUNDERSTORM ACTIVITY WILL INCREASE LATE WEEKEND AND EARLY NEXT
WEEK.
SHORT TERM /TODAY THROUGH FRIDAY/
LATEST OBJECTIVE ANALYSIS DEPICTS AN ELONGATED SUBTROPICAL RIDGE
EXTENDING FROM EASTERN AZ THROUGH THE EASTERN PACIFIC JUST OFF THE
COAST OF SOUTHERN CA WITH 500 MB HEIGHT FIELDS RANGING BETWEEN 594-
596DM. WITH THE RIDGING DIRECTLY OVERHEAD, VERY HOT TEMPERATURES
WILL CONTINUE TODAY ACROSS THE REGION WITH AFTERNOON HIGHS RANGING
BETWEEN 110-114 DEGREES ACROSS THE SOUTH-CENTRAL AZ LOWER DESERTS TO
111-116 DEGREES ACROSS THE WESTERN DESERTS. THESE AFTERNOON HIGHS
COMBINED WITH VERY WARM OVERNIGHT LOWS IN THE 80S TO AROUND 90
DEGREES IN THE PHOENIX METRO WILL CONTINUE TO RESULT IN AREAS OF
MAJOR HEATRISK. AS A RESULT, AN EXTREME HEAT WARNING REMAINS IN
ACROSS ALL OF THE LOWER DESERT LOCATIONS THROUGH THIS EVENING. THE
RIDGING WILL WEAKEN SLIGHTLY INTO FRIDAY, RESULTING IN SLIGHTLY
LOWER AFTERNOON HIGHS. HOWEVER, ACROSS WESTERN IMPERIAL COUNTY AND
THE LOWER COLORADO RIVER VALLEY AREA IN PARTICULAR, TEMPERATURES
WILL STILL TOP OUT BETWEEN 111-115 DEGREES WITH AREAS OF MAJOR
HEATRISK CONTINUING AND THUS HAVE ELECTED TO EXTEND THE EXTREME
HEAT WARNING THROUGH FRIDAY EVENING ACROSS THIS REGION. WE ALSO
HAVE ELECTED TO EXTEND THE EXTREME HEAT WARNING THROUGH FRIDAY FOR
THE PHOENIX AREA AS EVEN THOUGH AFTERNOON HIGHS WILL BE SLIGHTLY
COOLER, RANGING BETWEEN 109-112 DEGREES, EARLY MORNING LOWS WILL
START OUT VERY WARM NEAR 90 DEGREES, RESULTING IN AREAS OF MAJOR
HEATRISK CONTINUING. WITH GREATER SUBSIDENCE AND SLIGHTLY DRIER
AIR EXPECTED TODAY AND FRIDAY, THE OVERALL CONVECTIVE COVERAGE
WILL DECREASE WITH ACTIVITY RELEGATED MOSTLY ACROSS THE WHITE
MOUNTAINS INTO THE SOUTHEASTERN THIRD OF AZ.
LONG TERM /SATURDAY THROUGH TUESDAY/
AS MENTIONED IN PREVIOUS DISCUSSIONS, THE OVERALL WEATHER PATTERN
HEADING INTO THE WEEKEND AND NEXT WEEK WILL BECOME MORE FAVORABLE
FOR A MORE ACTIVE MONSOONAL PATTERN TO SET UP. THE SUBTROPICAL RIDGE
WILL QUICKLY MIGRATE NORTHEASTWARD INTO THE ROCKIES OVER THE WEEKEND
AND THEN SET UP OVER THE CENTRAL PLAINS EARLY NEXT WEEK WHILE
STRENGTHENING IN THE PROCESS. AS THIS WHOLE PATTERN EVOLUTION
MATERIALIZES, THE MID-LEVEL FLOW WILL SHIFT OUT OF THE EAST TO
SOUTHEAST. THIS WILL INTRODUCE STRONG MOISTURE TRANSPORT INTO THE
DESERT SOUTHWEST WITH THE LATEST EPS AND GEFS SHOWING PWATS
INCREASING TO AT LEAST 1.4-1.5" STARTING AS EARLY AS SUNDAY AND
REMAINING ABOVE 1.5" INTO NEXT WEEK.
MOISTURE ON SATURDAY WILL LIKELY REMAIN FAIRLY LIMITED ACROSS SOUTH-
CENTRAL AZ WITH LOW-LEVEL MIXING RATIOS REMAINING BETWEEN 9-10 G/KG,
WITH THE BETTER MOISTURE AND THUS THE BEST CONVECTIVE POTENTIAL
REMAINING RELEGATED TO THE HIGHER TERRAIN AND SOUTHEASTERN AZ. THERE
ARE STRONG INDICATIONS FROM THE LATEST GUIDANCE OF A STRONG
CONVECTIVE COMPLEX LIKELY TO DEVELOP OVER NORTHERN SONORA SATURDAY
EVENING, WHICH WILL LIKELY SEND OF POOL OF HIGHER MOISTURE INTO
CENTRAL AZ HEADING INTO SUNDAY WITH MIXING RATIOS SOLIDLY ABOVE 10
G/KG. AS A RESULT, SUNDAY LOOKS TO BE THE FIRST REAL POTENTIAL FOR
GREATER THUNDERSTORM ACTIVITY TO MATERIALIZE ACROSS THE SOUTH-
CENTRAL AZ LOWER DESERTS WITH NBM POPS SOLIDLY IN THE 30-50% RANGE.
WITH PWATS VALUES REMAINING ABOVE 1.5" ALONG WITH MIXING RATIOS
ABOVE 10 G/KG THROUGH THE FIRST HALF OF NEXT WEEK, THE POTENTIAL FOR
ADDITIONAL CONVECTIVE ACTIVITY WILL REMAIN IN PLACE AND LIKELY
EXPAND FURTHER WEST TO INCLUDE THE WESTERN DESERTS AS WELL WITH NBM
POPS RANGING BETWEEN 20-40% EACH DAY. WE WILL ALSO HAVE TO BE ON THE
LOOKOUT FOR ANY POTENTIAL EASTERLY WAVES THAT COULD ENHANCE THE
CONVECTIVE ACTIVITY, HOWEVER, PINPOINTING THE TRACK AND TIMING OF
THESE WAVES THIS FAR OUT IS VERY DIFFICULT. THEREFORE, HIGH
UNCERTAINTY EXISTS OF WHICH PARTICULAR DAYS NEXT WEEK HAVE THE
POTENTIAL TO BE MORE CONVECTIVELY ACTIVE. WITH THE INCREASING
MOISTURE AND POTENTIAL CLOUD COVER, AFTERNOON HIGH TEMPERATURES
THIS WEEKEND INTO EARLY NEXT WEEK WILL GRADUALLY RETREAT TO NEAR
TO SLIGHTLY ABOVE NORMAL LEVELS WITH WIDESPREAD MODERATE HEATRISK
IN PLACE.
AVIATION
UPDATED AT 1730Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
THE MAIN AVIATION FORECAST UNCERTAINTY WILL BE THE POTENTIAL FOR
AN OUTFLOW FROM DISTANT CONVECTION MOVING THROUGH REGION EARLY
TONIGHT. AS OF NOW, BEST TIMING LOOKS TO BE BETWEEN 05Z-08Z,
THOUGH TIMING MAY NEED TO BE ADJUSTED IN LATER TAF UPDATES. DUE TO
THE UNCERTAINTY OF THIS FEATURE, IT ONLY INCLUDED IN THE TAFS AS
TEMPO GROUP. NO SIGNIFICANT DUST IS EXPECTED IF AN OUTFLOW WERE TO
COME TO FRUITION, BUT SOME SLIGHT REDUCTIONS IN SURFACE VIS
CANNOT BE RULED OUT, MAINLY AT KIWA. OUTSIDE OF THIS, DIURNAL
TRENDS WILL BE OBSERVED THROUGH THE PERIOD, WITH THE TIMING OF THE
NIGHTLY/EARLY MORNING E'RLY SHIFT HIGHLY CONDITIONAL THE
ADVANCEMENT OF A POSSIBLE OUTFLOW. AFTERNOON GUSTS AROUND 20 KT
CAN BE EXPECTED. BESIDES SOME DISTANT CU FROM HIGH TERRAIN
THUNDERSTORMS, SKIES WILL BE MOSTLY CLEAR IN THE VICINITY OF THE
TERMINALS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
MULTIPLE ROUND OF BREEZY TO WINDY CONDITIONS, MAINLY AT KBLH, WILL
BE THE MAIN AVIATION CONCERN DURING THE NEXT 24 HOURS. GUST THERE
WILL HOVER AROUND 25 KT THIS AFTERNOON BEFORE RELAXING AFTER
SUNSET, THOUGH SUSTAINED SPEEDS ARE EXPECTED TO REMAIN ELEVATED.
THE NEXT ROUND OF BREEZINESS IS ANTICIPATED OVERNIGHT IN A WINDOW
BETWEEN 08Z-12Z, THIS TIME WITH GUSTS THAT MAY APPROACH 30 KT AT
TIMES. SPEEDS SHOULD ONCE AGAIN RELAX AROUND SUNRISE. AT KIPL,
GUSTS WILL NOT BE AS STRONG, NOR AS PROMINENT DURING THE FORECAST
WINDOW, BUT OBS AROUND 20 KT ARE LIKELY TO BE SEEN THIS EVENING,
AND MAYBE AGAIN FOR A BRIEF MOMENT OVERNIGHT. CLEAR SKIES WILL BE
COMMON THROUGH FRIDAY MORNING.
FIRE WEATHER
GUSTY AND ERRATIC THUNDERSTORM WINDS WITH ISOLATED LIGHTNING OVER
THE FAR EASTERN DISTRICTS THROUGH FRIDAY WILL BE THE MAIN FIRE
WEATHER CONCERN. OUTSIDE OF ANY POTENTIAL OUTFLOWS, WINDS SHOULD
FAVOR DIURNAL TRENDS WITH TYPICAL AFTERNOON BREEZINESS AROUND 20
MPH. SOME STRONGER AFTERNOON GUSTS BETWEEN 20-30 MPH WILL BE
COMMON THROUGH FRIDAY ALONG THE LOWER COLORADO RIVER VALLEY.
AFTERNOON RH VALUES BETWEEN 10-20% WILL BE COMMON ACROSS THE
REGION THROUGH SATURDAY. OVERNIGHT RECOVERIES WILL GENERALLY
RANGE BETWEEN 30-60% WITH THE UPPER END OF THE RANGE ACROSS THE
IMPERIAL VALLEY AND THE EASTERN DISTRICTS. TEMPERATURES ARE
EXPECTED TO RUN WELL ABOVE NORMAL TODAY, WITH THE LOWEST
ELEVATIONS REACHING BETWEEN 110-115 DEGREES BEFORE A VERY
GRADUAL COOL DOWN TAKES PLACE STARTING FRIDAY. MORE WIDESPREAD
MONSOONAL ACTIVITY IS LIKELY STARTING LATE THIS WEEKEND AND
CONTINUING INTO NEXT WEEK. MOISTURE LEVELS AND HUMIDITIES SHOULD
ALSO IMPROVE CONSIDERABLY HEADING INTO NEXT WEEK, ALLEVIATING
MUCH OF THE FIRE WEATHER CONCERNS.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...EXTREME HEAT WARNING UNTIL 8 PM MST FRIDAY FOR AZZ530-537-540-
542>544-546-548-550-551.
EXTREME HEAT WARNING UNTIL 8 PM MST THIS EVENING FOR AZZ531>534-
536-538-539-541-545-547-549-553>555-559-560-562.
CA...EXTREME HEAT WARNING UNTIL 8 PM PDT FRIDAY FOR CAZ562-566-567-
569-570.
EXTREME HEAT WARNING UNTIL 8 PM PDT THIS EVENING FOR CAZ564-565-
568.
SHORT TERM...LOJERO
LONG TERM...LOJERO
AVIATION...RW
FIRE WEATHER...LOJERO/KUHLMAN
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