240
FXUS65 KPSR 160021
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
521 PM MST MON JUN 15 2026
UPDATE...UPDATED 00Z AVIATION DISCUSSION
KEY MESSAGES
- TEMPERATURES AROUND 3 TO 8 DEGREES ABOVE DAILY NORMAL WILL
RESULT IN WIDESPREAD MODERATE HEAT RISK WITH ISOLATED POCKETS OF
MAJOR HEAT RISK AT TIMES, THROUGH THE MIDDLE OF THE WEEK.
- CHANCES FOR SHOWERS AND THUNDERSTORMS REMAIN IN THE FORECAST FOR
AT LEAST ONE MORE DAY, WITH THE BEST POTENTIAL FOCUSED OVER
FOOTHILL AND HIGH TERRAIN LOCATIONS, THOUGH LOWER DESERT STORMS
CANNOT BE RULED OUT.
- AN EASTERN PACIFIC AREA OF LOW PRESSURE WILL HELP TO DRY THE
REGION OUT WHILE ALSO PROVIDING COOLER TEMPERATURES DURING THE
BACK HALF OF THE WEEK AND INTO THE WEEKEND.
SHORT TERM /TODAY THROUGH TUESDAY/
CURRENT RAP40 500MB ANALYSIS SHOW REGION TODAY UNDER H5 HEIGHTS
BETWEEN 590-592DAM WITH THE CORE OF THE SUBTROPICAL HIGH OVER
NORTHWESTERN MEXICO/CENTRAL BAJA PENINSULA. AN AREA OF LOW PRESSURE
REMAINS OVER CENTRAL CALIFORNIA AND EXTENDING INTO THE EASTERN
PACIFIC WITH BROAD RIDGING IN THE PACIFIC NW COAST LINE. THE
INTERACTION BETWEEN THE SUBTROPICAL HIGH AND THE LOWER PRESSURE OVER
CA ARE HELPING KEEP MOISTURE MORE OR LESS TRAPPED HERE IN THE LOWER
DESERTS, WITH THIS MORNING'S 12Z SOUNDING SEEING EVEN A SLIGHT
INCREASE COMPARED TO YESTERDAY MORNING'S 12Z SOUNDING WITH A PWAT
VALUE OF 1.54", OR NEAR 200-225% OF NORMAL FOR EARLY JUNE. MORNING
MUCAPE WAS 672 J/KG WITH THE GFS COMPUTED MLCAPE PROJECTED TO BE
BETWEEN 750-1000 J/KG TO SOME AREAS NEAR 1500 J/KG. ADDITIONALLY,
GUIDANCE CONTINUES TO POINT TOWARDS FLOW ALOFT INCREASING ACROSS
CENTRAL AND EASTERN ARIZONA, THIS WOULD SET UP MORE FAVORABLE
CONDITIONS TO PROMOTE AND SUSTAIN UPDRAFTS. LIKE THE PAST FEW DAYS
OROGRAPHIC LIFT WILL CONTINUE TO BE THE MAIN TRIGGER FOR STORMS TO
BEGIN THEIR ASCENT, HOWEVER WITH THE CONDITIONS MENTIONED EARLIER,
ANY STORMS THAT DO DEVELOP IN THE HIGHER TERRAIN HAVE A BETTER
CHANCE OF SURVIVAL AND CAN MOVE FURTHER DOWN INTO THE VALLEY. WINDS
ALOFT THIS AFTERNOON HAVE ALREADY BEGUN TO SHIFT FROM THE WEST TO
OUT OF THE NORTHWEST, DUE TO THIS OUTFLOW BOUNDARIES ARE LIKELY TO
PUSH FURTHER DOWN WHERE POPS TODAY RANGE BETWEEN 20-30% ACROSS THE
WESTERN AND SOUTHERN MARICOPA COUNTY AND BETWEEN 10-20% ACROSS
EASTERN MARICOPA COUNTY, NORTHERN PINAL COUNTY AND INTO THE EASTERN
HIGHER TERRAIN. WHILE MOST AREAS TODAY WON'T SEE MUCH IN TERMS OF
ACCUMULATIONS, LOCALIZED AREAS WHERE STORMS CROP UP MAY SEE A FEW
HUNDREDTHS OF AN INCH. OTHERWISE OUTSIDE OF RAINFALL POTENTIAL,
OTHER IMPACTS WILL BE THE CHANCE FOR LIGHTNING AND BLOWING DUST IN
THE USUAL DUST PRONE AREAS.
BY TUESDAY THE MOISTURE WILL BEGIN TO SLOWLY DISSIPATE WITH PWATS
EXPECTED TO DROP TO 1.00-1.25", ALTHOUGH EVEN THOSE VALUES ARE 150-
180% OF NORMAL. IN ADDITION TO LOSING SOME OF THE MOISTURE, THE
REGION WILL BEGIN TO BE TAKEN OVER BY STRONGER RIDGING LEADING TO
MORE SUBSIDENCE AS THE LOW OVER CALIFORNIA DEGRADES, THIS WILL
SEVERELY LIMIT POTENTIAL FOR ANY CONVECTIVE ACTIVITY FOR TOMORROW
AFTERNOON. THE HIGHER TERRAIN AREAS MIGHT BE ABLE TO SQUEEZE AN
ISOLATED SHOWER OUT, HOWEVER, CURRENTLY MOST CAMS SHOW VERY LITTLE
TO NOTHING IN TERMS OF ACTIVITY EVEN IN THE HIGHER TERRAIN AREAS.
TEMPERATURES FOR TODAY AND TUESDAY AREN'T NEARLY AS EXCITING.
AFTERNOON HIGHS TODAY'S WILL BE BETWEEN 105F-111F AND THEN BETWEEN
107F-113F FOR TUESDAY AS RIDGING BUILDS OVER THE REGION. OVERNIGHT
LOWS WILL ALSO REMAIN IN THE MID 80S PROVIDING VERY LITTLE RELIEF.
CONTINUING THIS TREND OF ABOVE NORMAL HIGH AND LOW TEMPERATURES
KEEPS WIDESPREAD MODERATE TO LOCALIZED AREAS OF MAJOR HEATRISK IN
THE LOWER DESERTS. WITH THAT SAID REMEMBER THAT PROPER HEAT
PRECAUTIONS SHOULD BE USED IF PLANS TAKE YOU OUTSIDE FOR EXTENDED
PERIODS DURING THE NEXT COUPLE OF DAYS.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
THE REMAINDER OF THE WEEK LOOKS GENERALLY UNEXCITING, AT LEAST FOR
OUR AREA, AS DRY AIR FILTERS IN FROM WEDNESDAY ONWARD. THERE COULD
BE JUST ENOUGH LEFT OVER MOISTURE TO SQUEEZE OUT SOME SHOWERS OVER
SOUTHEAST ARIZONA OR HIGH TERRAIN AREAS TO OUR NORTH AND EAST, BUT
THE MAJORITY OF ACTIVITY SHOULD BE FOCUSED OVER TUCSON AND FLAGSTAFF
CWAS. SOMETHING A BIT PECULIAR IS THE PRESENCE OF POPS AND QPF FOR
THE PHOENIX METRO ON FRIDAY, EVEN THOUGH PWATS WILL BE FALLING
CLOSER TOWARD NEAR AND BELOW NORMAL FOR JUNE. MOISTURE AT THOSE
LEVELS WOULD LIKELY NOT EVEN BE ENOUGH TO GET HIGH TERRAIN STORMS,
LET ALONE LOWER DESERT RAINFALL. THIS COULD BE JUST AN ARTIFACT OF
THE INGESTED WPC RAINFALL FORECAST THAT GETS ADJUSTED WITH TIME, BUT
WE WOULD BE HARD PRESSED TO GET RAINFALL ON FRIDAY WITH DRY AIR
RUSHING IN. WHO KNOWS, MAYBE IF WE CAN GET ENOUGH SYNOPTIC LIFT WITH
AN APPROACHING EASTERN PACIFIC TROUGH TO INTERACT WITH STUBBORN
MOISTURE, SOME RAIN CHANCES CANNOT BE COMPLETELY RULED OUT, BUT AS
OF NOW, I LEAN MORE TOWARD THE DRIER SOLUTION.
SPEAKING OF THAT TROUGH, ITS MIGRATION CLOSER TO THE DESERT
SOUTHWEST BY THE LATTER HALF OF THE WEEK WILL HELP US "COOL" OFF A
BIT AS TEMPERATURES FALL CLOSER TO NORMAL, WITH PERHAPS SOME AREAS
EVEN SEEING BELOW NORMAL READINGS BY THE WEEKEND. NOW, THIS DOES NOT
MEAN WE GET A BREAK FROM THE TRIPLE DIGITS, BUT AT LEAST DAILY
FORECASTED HIGHS FALL CLOSER TO 99-108. NOT A MASSIVE AMOUNT OF
RELIEF, BUT ENOUGH TO BACK REGIONAL HEATRISK DOWN TO THE LOWER END
OF THE MODERATE CATEGORY. HEAT PRECAUTIONS WILL STILL NEED TO REMAIN
IN PLACE REGARDLESS. LOWER MOISTURE WITH THOSE COOLER TEMPS WILL
ALSO ALLOW FOR SOME MORE COMFORTABLE OVERNIGHT LOWS IN THE UPPER 60S
TO NEAR 80 DEGREES. SOMETHING THAT WILL HAVE TO MONITORED IS THE
POTENTIAL FOR ELEVATED FIRE WEATHER CONDITIONS AS THIS FEATURE WILL
INCREASE WINDS REGIONWIDE. STRENGTH OF GUSTS IS STILL UNCERTAIN AT
THIS TIME, BUT WITH VERY DRY AIR EXPECTED TO BE IN PLACE, IT WOULD
NOT TAKE MUCH WIND TO INCREASE FIRE DANGER.
AVIATION
UPDATED AT 0020Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
STRONG WINDS FROM A NORTHERLY OUTFLOW BOUNDARY DURING THE NEXT
COUPLE OF HOURS WILL BE THE MAIN AVIATION WEATHER ISSUE THROUGHOUT
THE TAF PERIOD. A NORTHERLY OUTFLOW IS CURRENTLY MOVING THROUGH
THE TERMINALS WITH POTENTIAL PEAK GUSTS UPWARDS OF 30 KTS
EXPECTED. CONDITIONS SHOULD IMPROVE AFTER 01-02Z WITH THE OVERALL
WIND PATTERN RESUMING THE MORE TYPICAL DIURNAL TENDENCIES WITH
WESTERLY WINDS THIS EVENING SHIFTING OUT OF THE EAST LATE
EVENING/OVERNIGHT PERIOD AND BACK OUT OF THE WEST LATE TUESDAY
MORNING. OCCASIONAL GUSTS BETWEEN 20-25 KTS WILL BE POSSIBLE
TUESDAY AFTERNOON. FEW-SCT MID TO HIGH LEVEL CLOUD DECKS WILL BE
COMMON THROUGHOUT THE PERIOD.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
NO MAJOR AVIATION WEATHER CONCERNS WILL EXIST FOR THE NEXT 24
HOURS UNDER FEW MID TO HIGH CLOUD DECKS. AT KIPL, SOUTHEAST WINDS
WILL SHIFT OUT OF THE WEST THIS EVENING BEFORE SHIFTING BACK OUT
OF THE SOUTHEAST DURING THE OVERNIGHT PERIOD. AT KBLH, WINDS WILL
FLUCTUATE BETWEEN THE SOUTH TO SOUTHWEST. WIND GUSTS UPWARDS OF
20-25 KTS WILL BE POSSIBLE AT KBLH THROUGH NEXT COUPLE OF HOURS.
FIRE WEATHER
ELEVATED MOISTURE LEVELS WILL RESULT IN ISOLATED TO SCATTERED
THUNDERSTORMS ONCE AGAIN THIS AFTERNOON AND EVENING, 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, THE OVERNIGHT PERIOD WILL OFFER
AT LEAST SOME MODEST RELIEF AS MAXRH 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 10-15% DURING THE AFTERNOONS.
BY MID TO LATE THIS WEEK WINDS WILL BEGIN TO PICK UP, MOSTLY
ALONG THE COLORADO RIVER VALLEY, AND EASTERN AZ HIGHER TERRAIN,
WHERE GUSTS BETWEEN 25-30 MPH MAY OCCUR. THIS CAN LEAD TO ELEVATED
FIRE WEATHER, ESPECIALLY AS MOISTURE BEGINS TO FILTER OUT OF THE
REGION.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...NONE.
CA...NONE.
SHORT TERM...RYAN
LONG TERM...RW
AVIATION...LOJERO
FIRE WEATHER...RW/RYAN
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