634  
FXUS65 KPSR 290459  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
959 PM MST SUN JUN 28 2026  
   
UPDATE...UPDATED 06Z 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 0455Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, AND KDVT:  
NO MAJOR AVIATION WEATHER CONCERNS UNDER CLEAR SKIES CAN BE  
EXPECTED THROUGHOUT THE TAF PERIOD. THE OVERALL WIND PATTERN WILL  
FOLLOW THE TYPICAL DIURNAL TENDENCIES WITH A PERIOD OF SOUTHERLY  
WINDS EXPECTED LATE MORNING BEFORE THE WESTERLY SHIFT. PEAK GUSTS  
NEAR 20 KTS WILL BE COMMON MONDAY AFTERNOON/EARLY EVENING.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
ELEVATED WINDS WILL CONTINUE TO BE THE MAIN WEATHER ISSUE  
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 BETWEEN 25-30 KTS WILL CONTINUE AT KIPL THROUGH  
THE NEXT COUPLE OF HOURS BEFORE SUBSIDING THROUGH THE OVERNIGHT  
PERIOD. ANOTHER ROUND OF GUSTY WINDS NEAR 20-25 KTS AT KBLH AND  
UPWARDS OF 25 KTS, OCCASIONALLY HIGHER, AT KIPL CAN BE EXPECTED  
ONCE AGAIN LATE MONDAY AFTERNOON/EVENING.  
 

 
   
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...NONE.  
CA...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ562-566.  
 

 
 

 
 
SHORT TERM...WHITTOCK  
LONG TERM...BERISLAVICH  
AVIATION...LOJERO  
FIRE WEATHER...WHITTOCK/BERISLAVICH  
 
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