320
FXUS65 KPSR 141225
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
525 AM MST SUN JUN 14 2026
KEY MESSAGES
- TEMPERATURES AROUND 3 TO 8 DEGREES ABOVE DAILY NORMALS WILL
RESULT IN WIDESPREAD MODERATE HEAT RISK, WITH ISOLATED POCKETS
OF MAJOR HEAT RISK AT TIMES, THROUGH THE MIDDLE OF NEXT WEEK.
- CHANCES FOR SHOWERS AND THUNDERSTORMS WILL EXIST THROUGH THE
REMAINDER OF THE WEEKEND AND INTO THE START OF THE UPCOMING
WEEK, WITH THE BEST CHANCES FOCUSED OVER HIGH TERRAIN AREAS AND
PORTIONS OF SOUTHEAST ARIZONA.
- BRIEF GUSTY WINDS FROM DISTANT OUTFLOWS AND LOW PROBABILITIES
FOR A THUNDERSTORM OR TWO OVER THE FOOTHILLS OF MARICOPA COUNTY
CANNOT BE RULED OUT TODAY AND AGAIN MONDAY DURING THE AFTERNOON
AND EVENING HOURS.
SHORT TERM /TODAY THROUGH MONDAY/
EARLY MORNING OBJECTIVE ANALYSIS REVEALS A BIT OF A MESS OF A
PATTERN OVER THE DESERT SOUTHWEST AS A NUMBER OF DIFFERENT WEATHER
REGIMES HOVER AROUND THE REGION. CLASHING AREAS OF LOW AND HIGH
PRESSURE CONTINUE TO FUNNEL ENHANCED MOISTURE FLUX INTO ARIZONA
AND SOUTHERN CALIFORNIA (THE MAIN REASON FOR SOME CONVECTIVE
ACTIVITY ON SATURDAY), WHILE A SEPARATE WEAK TROUGH FLOATS OVER
CENTRAL/NORTHERN CALIFORNIA. WITH PRESENCE OF THE FORMER TWO
FEATURES, MOISTURE LEVELS WILL REMAIN ELEVATED THROUGH TODAY AND
EVEN INTO MONDAY, WHICH WILL KEEP SHOWER AND THUNDERSTORM
POTENTIAL IN THE FORECAST, MAINLY FOR HIGH TERRAIN AREAS AND
PORTIONS OF SE ARIZONA, OVER THE NEXT FEW DAYS. MESOSCALE ANALYSIS
SHOWS PWATS RANGING FROM 0.9-1.3" WHICH IS STILL NOT QUITE ENOUGH
TO POP WIDESPREAD CONVECTIVE ACTIVITY FOR OUR FORECAST AREA GIVEN
HOW DRY AND HOT WE ARE THROUGHOUT A GOOD PORTION OF THE
ATMOSPHERIC COLUMN. HOWEVER, THERE ARE STILL SOME MINIMAL POPS
(10-15%) ACROSS THE FOOTHILLS OF MARICOPA COUNTY, PORTIONS OF
SOUTHERN GILA COUNTY, AND EVEN AREAS AROUND THE TABLE TOP
WILDERNESS THIS AFTERNOON AND EVENING. WHERE THE "BEST" POPS ARE,
AND HOW LIMITED THEY ARE, IS A GOOD INDICATOR OF HOW RELIANT
CONVECTION WILL ON OROGRAPHIC INFLUENCES GIVEN THE UNFAVORABLE
SYNOPTIC SETUP AND BARELY SUFFICIENT MOISTURE. MAIN IMPACTS WITH
ANY POTENTIAL SHOWER AND THUNDERSTORMS WILL BE OCCASIONAL
LIGHTNING AND GUSTY WINDS IN EXCESS OF 35 MPH. SOME LOCALIZED
AREAS OF BLOWING DUST CANNOT BE RULED OUT IF STORMS DO POP ALONG
THE BORDER OF SOUTHERN MARICOPA AND PINAL COUNTIES.
TRANSITIONING FROM THE WEEKEND INTO THE START OF THE UPCOMING WEEK,
SOME HI-RES GUIDANCE IS PICKING UP ON EARLY MORNING PRECIPITATION
ACTIVITY ACROSS LA PAZ, YUMA, AND WESTERN PORTIONS OF MARICOPA
COUNTIES. TAKING A CLOSER LOOK AT THE SYNOPTIC PATTERN, NOTHING
REALLY STANDS OUT AS TO WHAT MIGHT TRIGGER THESE MORNING SHOWERS.
ONE POSSIBLE EXPLANATION COULD BE A SUBTLE GRAVITY WAVE THAT GETS
KICKED OUT FROM DISTANT CONVECTION. HOWEVER, THERE ARE SOME
MODELS THAT SHOW VIRTUALLY NOTHING OVER THESE SAME AREAS, SO
CONFIDENCE REGARDING THIS EPISODE OF POTENTIAL RAIN IS QUITE LOW.
THIS UNCERTAINTY IS REFLECTED IN CURRENT POPS AS THEY CURRENTLY
MAX OUT AROUND 10-15%. THIS ACTIVITY LOOKS TO BE HIGHLY
CONDITIONAL ON HOW THINGS EVOLVE THIS AFTERNOON AND EVENING, BUT
EVEN IF THE "RAINIER" SOLUTIONS COME TO FRUITION, VERY LITTLE
IMPACTS CAN BE EXPECTED.
RAIN POTENTIAL MONDAY WILL NOT BE LIMITED TO JUST THE MORNING
HOURS AS LINGERING MOISTURE WILL KEEP PRECIP CHANCES OVER PARTS
OF THE REGION AS WE ADVANCE INTO THE AFTERNOON AND EVENING HOURS.
IN FACT, CHANCES, AT LEAST FOR OUR FORECAST AREA, DURING THIS
TIMEFRAME APPEAR SLIGHTLY BETTER (15-30%) COMPARED TO TODAY,
THOUGH COVERAGE IS NOT THAT MUCH BETTER AS THOSE CHANCES REMAIN
FOCUSED OVER SIMILAR AREAS MENTIONED ABOVE. AGAIN, NOTHING REALLY
STICKS OUT AS A TRIGGERING MECHANISM FOR CONVECTION, OTHER THAN
OROGRAPHIC LIFT, SO IT IS A BIT PUZZLING AS TO WHY CHANCES
INCREASE, BUT A DEEPER DIVE INDICATES THAT UPPER-LEVEL MASS SPEED
DIVERGENCE OVER EASTERN PORTIONS OF ARIZONA MIGHT BE THE KEY. WE
WILL ALSO SEE FLOW SWITCH MORE OUT OF THE W/NW, WHICH MAY ACTUALLY
ALLOW FOR THE PHOENIX METRO TO GET IN ON SOME RAINFALL ACTION AS
WELL. THIS SETUP SHOULD CREATE A MORE FAVORABLE PATTERN FOR
POTENTIAL OUTFLOWS OVER HIGH TERRAIN AREAS TO DESCEND TOWARD THE
LOWER DESERTS, TRIGGERING MORE CONVECTION, WHICH IS WHY CHANCES
FOR PHOENIX ARE BETTER FOR MONDAY AS WELL, BUT STILL REMAIN LOW
(10-15%) DUE THE HIGHLY DEPENDENT NATURE OF WHERE STORMS MAY POP.
EVEN WITH ALL THIS TALK OF RAIN WE CAN'T GIVE A FORECAST FOR THE
DESERT SOUTHWEST DURING THE LATE SPRING WITHOUT MENTIONING
TEMPERATURES. AFTER WE WITNESSED THE FIRST 110 DEGREE DAY AT
PHOENIX, WHICH OCCURRED RIGHT AROUND WHEN IT TYPICALLY DOES AS THE
AVERAGE FIRST DATE IT 6/11, IT LOOKS LIKE READINGS WILL BE MUCH
OF THE SAME AS READINGS HOVER BETWEEN 106-110 FOR THE METRO.
SIMILAR READINGS CAN BE EXPECTED FOR THE REMAINDER OF THE LOWER
DESERTS NOT ONLY FOR TODAY, BUT FOR MONDAY AS WELL AS DAY-TO-DAY
READINGS WILL NOT FLUCTUATE MUCH OVER DURING THE NEXT FEW DAYS.
LONG TERM /TUESDAY THROUGH SATURDAY/
MODELS INDICATE THAT MOISTURE WILL NOT COMPLETELY SCOUR OUT THROUGH
THE MIDDLE OF THE WEEK, ALLOWING FOR AT LEAST SOME DIURNALLY
DRIVEN SHOWER AND THUNDERSTORM ACTIVITY DURING THIS WINDOW ACROSS
THE SOUTHEASTERN PORTION OF ARIZONA AND SOME HIGH TERRAIN AREAS.
HOWEVER, GUIDANCE CONTINUES TO SHOW EASTERN PACIFIC RIDGING
STRETCHING INTO OUR FORECAST AREA, GENERATING A BROAD AREA OF
SUBSIDENCE ALOFT AND THEREFORE LIMITING NEAR-FUTURE RAINFALL FOR
AT LEAST MOST OF OUR FORECAST AREA. THIS AREA OF NEAR TO SLIGHTLY
ABOVE NORMAL HEIGHT ANOMALIES WILL HELP TO KEEP TEMPERATURES
AROUND 3-8 DEGREES ABOVE NORMAL THROUGH AT LEAST WEDNESDAY. BEYOND
THAT, WE BEGIN TO FLIP THE SCRIPT AS AN EASTERN PACIFIC TROUGH
DEVELOPS IN CONJUNCTION WITH THE NORTHWARD MIGRATION OF A SUB-
TROPICAL JET STREAK. THIS FEATURE WILL INCREASE WINDS REGIONALLY
AS THE SUBTROPICAL JET IMPARTS DEEP SOUTHWESTERLY FLOW, DECREASE
HEIGHTS ALOFT, AND SUBSTANTIALLY SCOUR OUT THE LOW LEVEL MOISTURE
ACROSS THE REGION. AS A RESULT, ANTICIPATE ELEVATED FIRE WEATHER
CONCERNS, ESPECIALLY FOR SOUTHEAST CA AND SOUTHWEST AZ,
TEMPERATURES MODERATING CLOSER TO DAILY NORMALS, AND THE DIURNALLY
DRIVEN SHOWER/STORM CHANCES OVER AZ HIGH TERRAIN TO END.
AVIATION
UPDATED AT 1225Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
GUSTY WEST WINDS THIS AFTERNOON FOLLOWED BY THE POTENTIAL FOR
STRONG, ABRUPT NORTHERLY OUTFLOW WINDS THIS EVENING AND LOW
CONFIDENCE ON VCSH/VCTS CONDITIONS WILL BE THE MAIN AVIATION
CONCERNS UNDER FEW-SCT MID TO HIGH DECKS. AFTER A PERIOD OF LIGHTER
E/SE OR VRB WINDS THIS MORNING, WEST WINDS WILL ESTABLISH BETWEEN 14-
17Z ACROSS THE TERMINALS AND LIKELY BECOME GUSTY BY THE LATTER HALF
OF THE AFTERNOON WITH GUSTS AROUND 20 KTS. CONVECTION WILL AGAIN
AFFECT HIGHER TERRAIN AREAS SUNDAY AFTERNOON WITH A FEW SHOWERS OR
ISOLATED STORMS POTENTIALLY REACHING THE NORTHERN FRINGES OF THE
PHOENIX METRO BY EARLY EVENING. CONFIDENCE IS MODERATE THAT MOST IF
NOT ALL TERMINALS WILL SEE AN ABRUPT WIND SWITCH OUT OF THE NORTH AS
AN OUTFLOW OVERSPREADS THE METRO AREA BETWEEN 01-04Z, WITH GUSTS
POTENTIALLY EXCEEDING 25 KTS BRIEFLY.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
NO MAJOR WEATHER CONCERNS WILL EXIST THROUGH MONDAY MORNING UNDER
MOSTLY CLEAR SKIES. CONFIDENCE IS GOOD THAT A SOUTHERLY WIND
COMPONENT WITH OCCASIONAL GUSTINESS WILL BE MAINTAINED AT KBLH WHILE
DIRECTIONS OSCILLATE BETWEEN SE AND SW/W AT KIPL.
FIRE WEATHER
ELEVATED MOISTURE LEVELS WILL RESULT IN ISOLATED CONVECTION THE
NEXT FEW AFTERNOONS, MAINLY FOR HIGHER TERRAIN AREAS, THAT WILL BE
CAPABLE OF PRODUCING GUSTY AND ERRATIC WINDS AND DRY LIGHTNING.
OUTSIDE OF ANY THUNDERSTORM OUTFLOWS, WINDS WILL BE DIURNALLY
DRIVEN WITH THE TYPICAL AFTERNOON AND EVENING UPSLOPE/UPVALLEY
BREEZINESS BETWEEN 15-25 MPH. ENHANCED MOISTURE WILL BRING SOME
BENEFIT AS MINRHS RANGE BETWEEN 15-20% FOR THE MAJORITY OF THE
REGION, WITH THE EXCEPTION BEING SE CALIFORNIA WHERE READINGS WILL
BE CLOSER TO 10%. FOR THOSE AREAS WITH BETTER MOISTURE, MAXRHS
WILL OFFER AT LEAST SOME MODEST RELIEF AS READINGS RISE TO 30-50%
EACH NIGHT. THOSE DRIER SPOTS FURTHER WEST HOWEVER WILL ONLY SEE
VALUES INCREASE TO AROUND 25%. MOISTURE SCOURS OUT DURING THE BACK
HALF OFF THE WEEK, WHICH WILL DECREASE DRY THUNDERSTORM
POTENTIAL, BUT DROP RHS CLOSER TO 10% DURING THE AFTERNOONS.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...NONE.
SHORT TERM...RW
LONG TERM...WHITTOCK/RW
AVIATION...WHITTOCK
FIRE WEATHER...RW
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