072
FXUS65 KPSR 072356
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
456 PM MST TUE JUL 7 2026
UPDATE
00Z AVIATION DISCUSSION.
KEY MESSAGES
- HOT TEMPERATURES CONTINUE THIS WEEK RESULTING IN AREAS OF MAJOR
HEAT RISK AND EXTREME HEAT WARNINGS THROUGH THURSDAY ACROSS LOWER
DESERT LOCATIONS.
- ISOLATED THUNDERSTORMS OVER HIGHER TERRAIN AREAS OF EASTERN
ARIZONA WILL SEND GUSTY OUTFLOW WINDS TOWARDS LOWER ELEVATIONS OF
SOUTH-CENTRAL ARIZONA THE NEXT COUPLE DAYS.
- THE WEATHER PATTERN WILL BECOME VERY FAVORABLE FOR MOISTURE IMPORT
AND MORE WIDESPREAD THUNDERSTORM ACTIVITY NEXT WEEK.
SHORT TERM /TODAY THROUGH THURSDAY/
EARLY AFTERNOON OBJECTIVE ANALYSIS DEPICTS A SPRAWLING SUBTROPICAL
RIDGE OVER THE SW CONUS WITH ONE PARTICULAR ANTI-CYCLONE CENTER
DIRECTLY OVER CENTRAL ARIZONA. H5 HEIGHTS CURRENTLY NEAR 594DM WILL
INCREASE SLIGHTLY TO NEAR 596DM WEDNESDAY AS THE CORE OF THE HIGH
PRESSURE SYSTEM CONTINUES TO RETROGRADE TOWARDS THE CALIFORNIA
COAST. MODEL AGREEMENT ON THIS EVOLUTION IS EXCELLENT YIELDING VERY
NARROW SPREAD IN NUMERICAL GUIDANCE, AND RESULTING IN TEMPERATURES
SOLIDLY 5F-10F ABOVE NORMAL THE NEXT FEW DAYS. EXTREME HEAT WARNINGS
REMAIN IN EFFECT DESPITE HOVERING BELOW DAILY RECORDS AND ONLY
COINCIDENT WITH PATCHY MAJOR HEATRISK OWING TO THE FACT THIS EPISODE
IS OCCURRING DURING THE PEAK OF CLIMATOLOGICAL TEMPERATURES. A
GRADUAL INCREASE IN BOUNDARY LAYER MOISTURE WILL ALSO RESTRICT THE
AMOUNT OF NOCTURNAL COOLING SUCH THAT EVEN MORNING LOWS ONLY RETREAT
INTO THE 80S/LOWER 90S.
WHILE THE DIRECT PASSAGE OF STRONG SUBTROPICAL RIDGING WOULD
TYPICALLY RESULT IN WIDESPREAD SUBSIDENCE, THIS WILL NOT ENTIRELY BE
THE CASE THE NEXT FEW DAYS. UPPER LEVEL SUPPORT IN THE FORM OF JET
LEVEL DIVERGENCE WILL ENCOURAGE DEEP CONVECTIVE UPDRAFTS OVER
MOUNTAINOUS AREAS OF EASTERN ARIZONA AS LOW LEVEL 7-9 G/KG MIXING
RATIOS WILL BE SUFFICIENT FOR SCATTERED THUNDERSTORM DEVELOPMENT.
SITTING UNDER THE RIDGE AXIS AND GIVEN THE LIMITED MOISTURE
AVAILABILITY, STORMS MAY BE MORE ISOLATED AND SHORT-LIVED THIS
AFTERNOON/EVENING, HOWEVER DCAPE VALUES IN EXCESS OF 1500 J/KG WILL
SUPPORT LOCALLY STRONG, GUSTY WINDS AND SEMI-ORGANIZED OUTFLOW
BOUNDARIES ATTEMPTING TO PROPAGATE WESTWARD.
IT'S UNLIKELY STRONG, GUSTY WINDS REACH INTO HIGHER POPULATION
CENTERS THIS EVENING, HOWEVER HREF MEMBERS INDICATE MORE AGGRESSIVE
STORM DEVELOPMENT WEDNESDAY WITH BETTER ORGANIZED OUTFLOWS CAPABLE
OF LONGER DURATION PROPAGATION. THERE IS ALSO A DISTINCT POSSIBILITY
OF MULTIPLE ORGANIZED OUTFLOW BOUNDARIES WEDNESDAY EVENING, AND IT'S
CONCEIVABLE BOUNDARY COLLISIONS COULD SPARK ADDITIONAL DEEP
CONVECTION, THOUGH LOW LEVEL MIXING RATIOS BELOW 10 G/KG WOULD
CERTAINLY LIMIT THIS POSSIBILITY OVER LOWER ELEVATIONS AND HIGH
RESOLUTION MODELING ONLY PARTIALLY ALLUDES TO THIS OUTCOME.
REGARDLESS, SOME GUSTS 25-35 MPH AND LOCALIZED BLOWING DUST APPEARS
MORE LIKELY TOMORROW VERSUS TODAY POSSIBLY SKIRTING THE SOUTHERN AND
EASTERN PARTS OF THE PHOENIX METRO. THUNDERSTORM ACTIVITY MAY
REVERT BACK TO AN ISOLATED MOUNTAIN EVENT THURSDAY AS THE NORTHERN
STREAM JET CORE SHIFTS SOUTH IN THE GREAT BASIN SUPPRESSING THE
MORE FAVORABLE DIVERGENCE ALOFT INTO NORTHERN MEXICO/SE ARIZONA.
LONG TERM /FRIDAY THROUGH MONDAY/
ABOVE NORMAL TEMPERATURES WITH AT LEAST HIGH-END MODERATE HEATRISK
IS FORECAST FOR FRIDAY, BEFORE GRADUAL COOLING AND EVENTUALLY A BIG
UPTICK IN MONSOON STORM ACTIVITY ARRIVES OVER THE WEEKEND INTO EARLY
NEXT WEEK. FORECAST HIGHS FRIDAY ARE STILL RANGING FROM 110-114
DEGREES ACROSS THE WESTERN LOWER DESERTS, WHILE LOWERING HEIGHTS
OVER CENTRAL AND EASTERN ARIZONA SHOULD ALLOW FOR HIGHS TO LOWER TO
108-112 DEGREES. LOW LEVEL MOISTURE IS ALSO SHOWN TO START
INCREASING AGAIN AS EARLY AS FRIDAY WITH MOISTURE STREAMING OFF THE
GULF OF CALIFORNIA. HOWEVER, DRIER AIR ALOFT WILL DILUTE SOME OF
THIS LOW LEVEL MOISTURE INCREASE AND IT'S LIKELY TO TAKE A COUPLE
DAYS FOR MOISTURE AND INSTABILITY TO INCREASE ENOUGH FOR STORM
POTENTIAL TO RAMP BACK UP. SHOWER AND STORM CHANCES ARE CURRENTLY
EXPECTED TO PICK UP ON SATURDAY ACROSS AT LEAST SOUTHEAST ARIZONA
WITH SOME POTENTIAL FOR DECAYING ACTIVITY INTO THE SOUTH-CENTRAL
ARIZONA LOWER DESERTS SATURDAY EVENING/NIGHT.
STARTING SUNDAY OR MONDAY, MODELS ARE REALLY SETTING UP THE REGION
TO BECOME QUITE ACTIVE AS THERE IS GOOD AGREEMENT SHIFTING THE HIGH
CENTER SOMEWHERE TO OUR NORTHEAST. GUIDANCE IS FAVORING A VERY LARGE
RIDGE WITH RECORD OR NEAR RECORD H5 HEIGHTS SETTING UP OVER THE
NORTHERN PLAINS BY SUNDAY. THE RIDGE IS EXPECTED TO BE VERY
EXPANSIVE STRETCHING AS FAR WEST AS THE FOUR CORNERS AREA AND AS FAR
EAST AS THE OHIO RIVER VALLEY. AS OF RIGHT NOW, THE LARGE SCALE FLOW
IS LIKELY TO BECOME BLOCKED WITH THIS RIDGE LASTING THROUGH MOST, IF
NOT ALL OF NEXT WEEK.
THE EXPECTED LARGE EXPANSE AND STRENGTH OF THIS RIDGE SHOULD BE
QUITE BENEFICIAL FOR INCREASING MOISTURE AND STORM CHANCES OVER MUCH
OF THE DESERT SOUTHWEST NEXT WEEK. ALTHOUGH UNCERTAINTY REMAINS,
ESPECIALLY WITH HOW MUCH MOISTURE AND WITH ANY POTENTIAL
DISTURBANCES THAT ARE LIKELY TO MOVE OVER OR NEAR OUR REGION, WE ARE
ANTICIPATING OUR FIRST DECENT PERIOD OF MONSOON ACTIVITY NEXT WEEK.
IT IS TOO EARLY TO SPECULATE ON WHICH DAYS WILL BE THE MOST ACTIVE,
BUT NBM/WPC POPS FOR SUNDAY ARE ALREADY AS HIGH AS 30-40% OVER
EASTERN AND SOUTH-CENTRAL ARIZONA. ONCE THE MONSOON ACTIVITY KICKS
INTO GEAR, TEMPERATURES SHOULD ALSO BEGIN TO DIP CLOSER TO SEASONAL
NORMALS.
AVIATION
UPDATED AT 1740Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
NO MAJOR WEATHER CONCERNS ARE EXPECTED THROUGH THE TAF PERIOD.
WINDS WILL CONTINUE TO BE OUT OF THE WEST THROUGH THIS AFTERNOON
AND EVENING WITH A LOW CHANCE OF A BRIEF EASTERLY SHIFT DUE TO AN
OUTFLOW FROM THE EAST. HOWEVER, CURRENT ANALYSIS SHOW THE OUTFLOW
WEAKENING SO CONFIDENCE IS LOW THAT IT WILL REACH THE TERMINALS.
OTHERWISE, AN ESTABLISHED EASTERLY SHIFT WON'T BE UNTIL JUST PAST
MIDNIGHT TONIGHT, WHERE PERIODS OF VRB MAY ALSO BE POSSIBLE
THROUGH THE OVERNIGHT HOURS. TOMORROW AFTERNOON WILL BE ALMOST
IDENTICAL TO TODAY'S WITH AN EARLY WESTERLY SHIFT AND GUSTS IN THE
MID TEENS. FEW MID TO HIGH LEVEL CLOUDS WILL PERSIST.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
SOME MINOR GUSTY WINDS WILL CONTINUE TO BE THE MAIN AVIATION
CONCERN THROUGHOUT THE TAF PERIOD UNDER CLEAR SKIES. WINDS AT
KIPL WILL FAVOR THE SE THROUGH THE AFTERNOON BEFORE SWITCHING
AROUND TO THE SW THIS EVENING. AT KBLH, WINDS WILL FLUCTUATE
BETWEEN THE SSE TO SW. OVERALL SUSTAINED SPEEDS WILL REMAIN AOB 12
KTS, WITH SOME OCCASIONAL AFTERNOON/EVENING GUSTS NEAR 20 KTS.
FIRE WEATHER
GUSTY AND ERRATIC THUNDERSTORM WINDS WITH ISOLATED LIGHTNING OVER
THE FAR EASTERN DISTRICTS THE NEXT FEW AFTERNOONS WILL BE THE MAIN
FIRE WEATHER CONCERN. OUTSIDE OF ANY POTENTIAL OUTFLOWS, WINDS
SHOULD FAVOR LIGHT AND DIURNAL TRENDS WITH TYPICAL AFTERNOON
BREEZINESS AROUND 20 MPH. AFTERNOON RH VALUES BETWEEN 10-15% WILL BE
COMMON ACROSS THE REGION. OVERNIGHT RECOVERIES WILL OFFER ONLY
LIMITED TO MODEST RELIEF AS MAXRH VALUES RANGE GENERALLY BETWEEN 20-
45%. TEMPERATURES ARE EXPECTED TO RUN WELL ABOVE NORMAL THROUGH THE
MIDDLE OF THE WEEK, WITH THE LOWEST ELEVATIONS REACHING BETWEEN 110-
115 DEGREES. A DECREASE IN MONSOON ACTIVITY IS LIKELY LATE WEEK,
BEFORE PICKING UP AGAIN AND BECOMING MORE WIDESPREAD BY EARLY NEXT
WEEK. MOISTURE LEVELS AND HUMIDITIES SHOULD ALSO IMPROVE
CONSIDERABLY BY EARLY NEXT WEEK, ALLEVIATING MUCH OF THE FIRE
WEATHER CONCERNS.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...EXTREME HEAT WARNING UNTIL 8 PM MST THURSDAY FOR AZZ530>534-
536>551-553>555-559-560-562.
CA...EXTREME HEAT WARNING UNTIL 8 PM PDT THURSDAY FOR CAZ562-564>570.
SHORT TERM...18
LONG TERM...KUHLMAN
AVIATION...RYAN/SMITH
FIRE WEATHER...KUHLMAN
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