539
FXUS65 KPSR 282303
AFDPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
403 PM MST SUN JUN 28 2026
UPDATE...UPDATED 00Z AVIATION DISCUSSION
KEY MESSAGES
- UNUSUALLY STRONG WINDS WILL IMPACT THE REGION TODAY AND MONDAY
RESULTING IN CRITICAL TO NEAR CRITICAL FIRE WEATHER CONDITIONS
AND POTENTIALLY SOME BLOWING OR LOFTED DUST.
- BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE MAJORITY OF
THE UPCOMING WORK WEEK.
- MORE TRANQUIL WEATHER CONDITIONS AND A SLOW WARMING TREND WILL
ARRIVE DURING THE LATTER HALF OF THIS UPCOMING WEEK.
SHORT TERM /TODAY THROUGH MONDAY/
THE FORECAST REMAINS LARGELY ON TRACK, WITH LONGWAVE TROUGHING
ESTABLISHED AND CONTINUING TO DEEPEN OVER THE WESTERN CONUS. A
COUPLE CENTERS OF VORTICITY/UPPER LOWS CAN BE DISTINGUISHED UPON
ANALYSIS OF MIDLEVEL WATER VAPOR IMAGERY, ONE SETTLING OVER THE
GREAT BASIN AND A SECOND TO ITS NORTHEAST OVER FAR NORTHERN
MONTANA AT THIS HOUR. TEMPERATURES ALOFT AND MIDLEVEL HEIGHTS ARE
ANOMALOUSLY LOW, AROUND CLIMATOLOGICAL MINIMUMS FOR THIS TIME OF
YEAR OVER/NEAR THE GREAT BASIN ASSOCIATED WITH THE FIRST VORTICITY
CENTER NEAR THE BASE OF THE LONGWAVE TROUGH. UNSURPRISINGLY, THE
FLOW ALOFT IS ALSO ANOMALOUSLY STRONG AROUND THE BASE OF THIS
TROUGH, BRINGING NAEFS MEAN 700 MB WIND SPEEDS AROUND 30-40 KTS
ACROSS MUCH OF NORTHERN/EASTERN AZ THROUGH TODAY, NEAR CFSR
CLIMATOLOGICAL MAXIMUM VALUES. DESPITE JET ENERGY AND HEIGHT
PACKING OVER THE REGION DIMINISHING SINCE THEIR PEAKS YESTERDAY,
DEEP MIXING HEIGHTS TYPICAL FOR THIS TIME OF YEAR WILL HELP TAP
THE HIGHER MOMENTUM AIR ALOFT AND REALIZE GUSTS TO BETWEEN 30-40
MPH OVER PORTIONS OF THE TONTO NF AND SOUTHERN GILA COUNTY THIS
AFTERNOON INTO THE EARLY EVENING, AND THIS, COUPLED WITH LOW RH
AND PRIMED FUELS WILL RESULT IN ANOTHER DAY OF VERY HIGH FIRE
DANGER. THUS, A RED FLAG WARNING REMAINS IN EFFECT THROUGH 8 PM
MST THIS EVENING FOR THE AFOREMENTIONED AREA. WIDESPREAD AFTERNOON
BREEZINESS WILL CONTINUE TODAY, WITH GUSTS TO BETWEEN 20-30 MPH
COMMON TODAY AND STRONGER GUSTS IN THE TYPICALLY WIND PRONE AREAS
OF FAR WESTERN IMPERIAL COUNTY, WHERE A WIND ADVISORY REMAINS IN
EFFECT THROUGH 11 PM PDT THIS EVENING. WINDS WILL DIMINISH FURTHER
MONDAY, BUT WIDESPREAD AFTERNOON BREEZINESS IS STILL EXPECTED,
AND ANOTHER WIND HEADLINE MAY BE NEEDED FOR THE SOUTHWEST CORNER
OF IMPERIAL COUNTY FOCUSED FROM LATE AFTERNOON INTO THE OVERNIGHT
HOURS.
WHILE THE BASE OF WESTERN CONUS LONGWAVE TROUGHING SETTLES OVER
THE REGION, MIDLEVEL HEIGHTS WILL CONTINUE TO DECREASE, SUPPORTING
UNUSUALLY "COOL" TEMPERATURES FOR LATE JUNE. IN FACT, ENSEMBLE
MEAN H5 HEIGHTS ARE FORECAST TO BOTTOM OUT SOMETIME LATE MONDAY OR
OTHERWISE DURING THE FIRST HALF OF THE WORK WEEK IN A 579-584 DAM
RANGE ACROSS THE FORECAST AREA, BETWEEN THE 3RD AND 10TH
PERCENTILES OF CLIMATOLOGY. MEANWHILE, DEEP SOUTHWESTERLY FLOW
WILL CONTINUE TO PROMOTE DRYING THROUGHOUT THE COLUMN RESULTING IN
ENSEMBLE MEAN PWATS BELOW 50% OF NORMAL FOR LATE JUNE/EARLY JULY
ACROSS THE ENTIRE STATE AS WE HEAD INTO THE MIDDLE OF THE WEEK.
MINIMAL (IF ANY) CLOUD COVER AND VERY LOW HUMIDITIES WILL PROMOTE
EXCELLENT OVERNIGHT RADIATIVE COOLING, RESULTING IN OVERNIGHT LOWS
MUCH COOLER THAN DAILY NORMALS, IN THE 60S AND LOWER 70S (EXCEPT
WARMER IN URBAN AREAS) ACROSS THE LOWER DESERTS AS EARLY AS MONDAY
MORNING. THESE UNSEASONABLY COOL OVERNIGHT LOWS WILL BE FOLLOWED
BY AFTERNOON HIGHS IN THE UPPER 90S TO LOWER 100S, BETWEEN 4 AND
10 DEGREES BELOW THE DAILY NORMALS ACROSS THE LOWER DESERTS.
LONG TERM /TUESDAY THROUGH SATURDAY/
BY TUESDAY THE PACIFIC TROUGH WILL SETTLE OVER WESTERN CONUS
ALLOWING FOR NEGATIVE HEIGHT ANOMALIES TO REMAIN IN PLACE OVER OUR
REGION. THE PACIFIC TROUGH AND CORRESPONDING NEGATIVE HEIGHT
ANOMALIES WILL REMAIN IN PLACE THROUGH AT LEAST WEDNESDAY. THIS
WILL RESULT IN TEMPERATURES (BOTH MORNING LOWS AND AFTERNOON HIGH)
SEVERAL DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. AFTERNOON
HIGH TEMPERATURES ARE FORECASTED TO BE IN THE UPPER 90S TO AROUND
102 DEGREES ACROSS THE LOWER DESERTS AND IN THE LOW TO MID 90S
ACROSS THE HIGHER TERRAIN. MORNING LOWS ARE FORECASTED TO BE IN
THE MID 60S TO MID 70S ACROSS THE REGION. ENSEMBLE MODEL GUIDANCE
REMAINS IN GOOD AGREEMENT ON THE OVERALL SYNOPTIC PATTERN THROUGH
THIS UPCOMING WEEK WITH HIGH PRESSURE SLOWLY STARTING TO PUSH BACK
INTO THE DESERT SOUTHWEST FROM THE EAST AND THE AFOREMENTIONED
PACIFIC TROUGH LIFTING NORTH/NORTHEASTWARD. AS A RESULT, H5
HEIGHTS ALOFT WILL START TO INCREASE LEADING TO A GRADUAL WARMING
TREND. THE LATEST NBM HAS TEMPERATURES RETURNING TO NEAR TO
SLIGHTLY BELOW NORMAL BY THE END OF THE UPCOMING WORKWEEK. THE
HIGH PRESSURE SYSTEM WILL CONTINUE TO PUSH INTO OUR REGION NEXT
WEEKEND WITH H5 HEIGHTS ALOFT CONTINUING TO RISE. BY NEXT WEEKEND
AFTERNOON HIGH TEMPERATURES ARE FORECASTED TO GO BACK ABOVE NORMAL
AND BE IN THE 105-110 DEGREE RANGE.
ADDITIONALLY WITH THE PACIFIC TROUGH SETTLING OVER THE REGION ON
TUESDAY AND WEDNESDAY AND THEN RIDGING SLOWLY BUILDING BACK IN
DURING THE LATTER HALF OF THE WEEK, THE BREEZY TO WINDY CONDITIONS
WILL TAPER OFF WITH ONLY SOME MINOR AFTERNOON BREEZY CONDITIONS
EXPECTED ACROSS THE LOWER CO RIVER VALLEY AND THE HIGHER TERRAIN
EAST OF PHOENIX. VERY DRY CONDITIONS WILL ALSO REMAIN IN PLACE AND
THUS THERE WILL BE NO RAINFALL CHANCES THROUGH THIS UPCOMING WEEK.
AVIATION
UPDATED AT 2300Z.
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:
ELEVATED GUSTS WILL BE THE MAIN WEATHER ISSUE UNDER CLEAR SKIES
THROUGHOUT THE TAF PERIOD. WEST TO SOUTHWEST WINDS WITH GUSTS
UPWARDS OF 20-25 KTS WILL CONTINUE THROUGH EARLY THIS EVENING
BEFORE SUBSIDING AFTER SUNSET. LIGHT EASTERLY WINDS WILL
MATERIALIZE OVERNIGHT AND PERSIST INTO EARLY MONDAY MORNING
BEFORE SHIFTING OUT OF THE WEST DURING THE EARLY AFTERNOON HOURS
WITH A PERIOD OF SOUTHERLY WINDS EXPECTED MID/LATE MORNING.
AFTERNOON GUSTS ON MONDAY WILL BE SLIGHTLY LOWER, NEAR 20 KTS.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:
STRONG, GUSTY WINDS, ESPECIALLY AT KIPL, WILL BE THE MAIN WEATHER
ISSUE UNDER CLEAR SKIES THROUGHOUT THE TAF PERIOD. AT KIPL, WINDS
WILL GENERALLY BE OUT OF THE WEST WHILE AT KBLH, WINDS WILL
FLUCTUATE OUT OF THE SOUTH TO SOUTHWEST. GUSTS NEAR 25 KTS WILL
CONTINUE THROUGH SUNSET AT KBLH WHILE GUSTS UPWARDS OF 30 KTS WILL
CONTINUE AT KIPL THROUGH THE EVENING HOURS BEFORE SUBSIDING
OVERNIGHT. THE STRONG, GUSTY WINDS WILL LIKELY RESULT IN SOME
LOFTED DUST WITH MINOR IMPACTS TO SLANTWISE VISIBILITY.
FIRE WEATHER
ELEVATED TO CRITICAL FIRE DANGER WILL CONTINUE THROUGH AT LEAST
MONDAY DUE TO LOW HUMIDITY, VERY WARM TEMPERATURES, BREEZY
SOUTHWEST WINDS DURING THE AFTERNOONS/EARLY EVENINGS, AND VERY
RECEPTIVE DRY FUELS. A RED FLAG WARNING REMAIN IN EFFECT THROUGH
THIS (SUNDAY) EVENING FOR THE EASTERN DISTRICTS. AFTERNOON
MINIMUM HUMIDITIES BETWEEN 8-15% THROUGH TUESDAY WILL DROP TO A
5-10% RANGE BEGINNING WEDNESDAY. POOR TO FAIR OVERNIGHT
RECOVERIES BETWEEN 25-45% THROUGH WEDNESDAY NIGHT WILL DECREASE
INTO A 15-30% RANGE THURSDAY NIGHT. WIND GUSTS OF 25-35 MPH AND
LOCALLY STRONGER ARE EXPECTED TO LINGER INTO THIS EVENING. THESE
WINDY AND VERY DRY CONDITIONS WILL COMBINE WITH THE VERY DRY FUELS
TO CREATE A RISK OF EXTREME FIRE BEHAVIOR. WINDS WILL GRADUALLY
START TO DIMINISH DURING THE BEGINNING OF THE WORKWEEK.
TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE MAJORITY OF THE
UPCOMING WORKWEEK, WITH LOWER DESERT HIGHS AROUND 100F THROUGH
MIDWEEK.
PSR WATCHES/WARNINGS/ADVISORIES
AZ...RED FLAG WARNING UNTIL 8 PM MST THIS EVENING FOR AZZ133.
CA...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ562.
WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ566.
SHORT TERM...WHITTOCK
LONG TERM...BERISLAVICH
AVIATION...LOJERO
FIRE WEATHER...WHITTOCK/BERISLAVICH
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