420  
FXUS65 KPSR 251736  
AFDPSR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PHOENIX AZ  
1036 AM MST WED JUN 25 2025  
   
UPDATE  
UPDATED 18Z AVIATION DISCUSSION  
 
 
   
KEY MESSAGES  
 
- TEMPERATURES WILL AGAIN BE A FEW DEGREES BELOW NORMAL TODAY,  
BEFORE NEAR TO ABOVE NORMAL READINGS RETURN BY FRIDAY  
 
- DRY CONDITIONS WILL OVERALL PREVAIL THROUGH THE WEEKEND WITH  
DAILY LIGHT AFTERNOON AND EVENING BREEZES  
 
- WIDESPREAD MODERATE HEATRISK IS EXPECTED BY THIS WEEKEND, WITH  
LOCALIZED MAJOR HEATRISK AND HIGHS AT OR JUST ABOVE 110 DEGREES  
BY THE START OF NEXT WEEK  
 
 
   
DISCUSSION  
 
FOR THE START OF LAST WEEK OF JUNE, THE WEATHER PATTERN HAS BEEN  
QUITE FAVORABLE TO KEEP TEMPERATURES FROM GETTING OUT OF HAND.  
LOOKING BACK OVER THE LAST SEVERAL YEARS, WE ACTUALLY HAVE NOT HAD  
A BAD HEATWAVE DURING THE LAST WEEK OF JUNE. THAT'S NOT TO SAY IT  
WASN'T HOT, AS THE LAST WEEK OF JUNE IN 2024 SAW AVERAGE  
TEMPERATURES OF AROUND SIX DEGREES ABOVE NORMAL LARGELY BECAUSE  
OF VERY WARM OVERNIGHT TEMPERATURES DUE TO AN EARLY INFLUX OF  
MOISTURE. HOWEVER, WE CAN AT LEAST SAY WE HAVE NOT HAD A 115  
DEGREE DAY IN PHOENIX DURING THE LAST WEEK OF JUNE SINCE 2017.  
THIS COULD CHANGE THIS YEAR AS WE HAVE 114 DEGREES FORECAST FOR  
MONDAY. THE LAST SEVERAL DAYS HAVE BEEN AT OR JUST BELOW NORMAL  
DUE TO A STALLED OUT TROUGH CENTERED JUST TO OUR NORTHWEST.  
HOWEVER, THIS TROUGH IS BEGINNING TO FILL AND ALLOWING THE AIR  
MASS OVER OUR REGION TO GRADUALLY WARM. THIS WILL CONTINUE TO  
HAPPEN THROUGH FRIDAY WITH H5 HEIGHTS RISING FROM 582-585DM TODAY  
TO 588-590DM ON FRIDAY. FORECAST HIGHS BY THURSDAY REACH INTO THE  
NORMAL RANGE AND THEN ABOVE NORMAL ON FRIDAY WITH READINGS TOPPING  
OUT BETWEEN 105-108 DEGREES ACROSS THE LOWER DESERTS. ANY  
MOISTURE WILL CONTINUE TO MAINLY BE CONFINED TO NEW MEXICO WITH  
ONLY VERY MARGINAL MOISTURE SEEPING INTO FAR EASTERN ARIZONA  
PROVIDING THE POTENTIAL FOR A FEW ISOLATED AFTERNOON SHOWERS OR  
WEAK THUNDERSTORMS NEAR THE STATELINE EACH DAY THROUGH FRIDAY.  
 
STARTING THIS WEEKEND, THE RIDGE IS FORECAST TO SET UP DIRECTLY  
OVER THE REGION, LIKELY CENTERED OVER EASTERN ARIZONA AND WESTERN  
NEW MEXICO. THE RIDGE IS ALSO EXPECTED TO STRENGTHEN BY SUNDAY  
WITH H5 HEIGHTS PEAKING BETWEEN 592-594DM FOR SUNDAY AND MONDAY.  
FORTUNATELY, THE FORECAST STRENGTH OF THE RIDGE IS NOT ABNORMALLY  
STRONG FOR THIS TIME OF YEAR, BUT IT SHOULD BE ENOUGH TO PUSH  
DAYTIME HIGHS TO JUST ABOVE 110 DEGREES ON SUNDAY BEFORE LIKELY  
PEAKING BETWEEN 110-114 DEGREES MONDAY. IF GUIDANCE IS  
UNDERPLAYING THE STRENGTH OF THE RIDGE, THAT COULD PUSH HIGHS UP  
ANOTHER COUPLE OF DEGREES WITH SOME LOCATIONS POTENTIALLY REACHING  
115 DEGREES MONDAY. AS TEMPERATURES PUSH TO ABOVE NORMAL BY THE  
WEEKEND, WE WILL SEE WIDESPREAD MODERATE HEATRISK DEVELOP WITH  
EVEN SOME LOCALIZED MAJOR HEATRISK POSSIBLE FOR SUNDAY AND MONDAY.  
 
ENSEMBLE GUIDANCE THEN SUGGESTS THE RIDGE WILL BEGIN TO SHIFT MORE  
TO THE NORTH, CENTERING ITSELF OVER THE FOUR CORNERS AREA BY NEXT  
TUESDAY. ONCE THIS SHIFT OCCURS, IT SHOULD ALLOW FOR THE FLOW IN  
THE LOWER LEVELS TO TURN OUT OF THE SOUTHEAST INTO MUCH OF  
ARIZONA. IF GUIDANCE IS CORRECT WITH PUSHING THE HIGH CENTER OVER  
THE FOUR CORNERS AREA, IT WOULD ALLOW FOR A GRADUAL UPTICK IN  
MOISTURE ACROSS ARIZONA NEXT WEEK AND LIKELY OUR FIRST DECENT  
CHANCES OF MONSOON CONVECTION BY AROUND THE MIDDLE PART OF NEXT  
WEEK. SOME OF THIS WILL ALSO DEPEND ON A WEAK TROUGH THAT IS SHOWN  
SETTING UP JUST TO OUR NORTHWEST. FOR NOW, THERE REMAINS A GOOD  
DEAL OF UNCERTAINTY WITH THE PLACEMENTS OF THE HIGH CENTER AND THE  
TROUGH, ALONG WITH HOW MUCH AND WHEN THE MOISTURE ADVECTS INTO  
OUR REGION. WE COULD START TO SEE SOME ISOLATED TO SCATTERED  
EASTERN ARIZONA HIGHER TERRAIN CONVECTION AS EARLY AS MONDAY OR  
TUESDAY WITH SOME POTENTIAL FOR CONVECTION INTO THE LOWER DESERTS  
AS EARLY AS NEXT WEDNESDAY OR THURSDAY.  
 
 
   
AVIATION  
UPDATED AT 1730Z.  
 
SOUTH CENTRAL ARIZONA INCLUDING KPHX, KIWA, KSDL, KDVT:  
NO MAJOR AVIATION CONCERNS. WINDS WILL FOLLOW TYPICAL DIURNAL  
TRENDS. THE FAMILIAR AFTERNOON GUSTS WILL BE MOSTLY DORMANT TODAY,  
ESPECIALLY COMPARED TO THE PAST SEVERAL DAYS, BUT BRIEF PERIODS OF  
SPEEDS IN THE LOW TO MID TEENS COULD STILL BE POSSIBLE. WHILE FEW-  
SCT CLOUDS CAN BE SEEN IN THE DISTANCE OUR AREA WILL REMAIN  
MOSTLY CLEAR THROUGHOUT THE TAF PERIOD.  
 
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH:  
NO AVIATION CONCERNS ARE EXPECTED THROUGHOUT THIS TAF PERIOD.  
WINDS WILL FOLLOW TYPICAL DIURNAL TRENDS WITH SPEEDS GENERALLY AOB  
10 KTS. WHILE LIKELY NOT DIRECTLY IMPACTING SFC VISIBILITIES,  
LOFTED SMOKE/HAZE MAY OCCASIONALLY AFFECT SLANTWISE VISIBILITIES  
DURING THE MORNING AND LATE AFTERNOON/EVENING HOURS AT KIPL. OTHER  
THAN THE LOFTED SMOKE/HAZE CLEAR SKIES WILL PERSIST THROUGH THE  
TAF PERIOD.  
 
 
   
FIRE WEATHER  
 
NO SIGNIFICANT FIRE WEATHER CONCERNS ARE EXPECTED OVER THE NEXT  
FEW DAYS. TEMPERATURES WILL CONTINUE TO GRADUALLY WARM DAY-TO-  
DAY, BUT READINGS SHOULD REMAIN NEAR TO BELOW NORMAL THROUGH  
THURSDAY. MINRH VALUES WILL ONLY RANGE BETWEEN 5-15% AND  
OVERNIGHT RECOVERIES WILL NOT OFFER MUCH RELIEF AS VALUES HOVER  
BETWEEN 20-40%. WINDS WILL FOLLOW FAMILIAR DIURNAL TRENDS WITH  
TYPICAL AFTERNOON BREEZINESS, GUSTING MAINLY BETWEEN 15-20 MPH. BY  
THE WEEKEND, TEMPERATURES WILL WARM TO ABOVE NORMAL WITH HIGHS  
POTENTIALLY PEAKING ABOVE 110 DEGREES ACROSS THE LOWER DESERTS BY  
SUNDAY. EVENTUALLY, THE WEATHER PATTERN SHOULD BECOME MORE  
FAVORABLE FOR INCREASING MOISTURE AND AT LEAST SOME SCATTERED  
HIGH TERRAIN SHOWERS AND THUNDERSTORMS BY AROUND NEXT TUESDAY.  
THIS MAY INITIALLY RESULT A DAY OR TWO OF DRY LIGHTNING CONCERNS  
BEFORE MOISTURE AND RAINFALL CHANCES INCREASES LATER NEXT WEEK.  
 
 
   
PSR WATCHES/WARNINGS/ADVISORIES  
 
AZ...NONE.  
CA...NONE.  
 
 
 
 
DISCUSSION...KUHLMAN  
AVIATION...RYAN/RW  
FIRE WEATHER...KUHLMAN  
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