489  
FXUS65 KTWC 272148  
AFDTWC  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TUCSON AZ  
248 PM MST FRI JUN 27 2025  
 
SYNOPSIS...AFTERNOON AND EVENING CHANCES FOR SHOWERS AND  
THUNDERSTORMS CONTINUE THIS AFTERNOON SOUTH AND EAST OF TUCSON,  
MAINLY ALONG THE INTERNATIONAL BORDER EAST OF NOGALES AND CLOSER TO  
THE NEW MEXICO BORDER. TEMPERATURES BECOME HOTTER THIS WEEKEND AS  
CONDITIONS DRY OUT. MONSOONAL MOISTURE IS EXPECTED TO INCREASE NEXT  
WEEK WITH INCREASING PRECIPITATION CHANCES, ESPECIALLY THE SECOND  
HALF OF THE WEEK INCLUDING AROUND INDEPENDENCE DAY.  
 

 
   
KEY MESSAGES
 
 
-TEMPERATURES WILL BE ON THE INCREASE THIS WEEKEND, PEAKING MONDAY  
WITH HIGHS OF 108 TO 112 DEGREES IN THE DESERTS INCLUDING TUCSON AND  
UPPER GILA RIVER VALLEY. AN EXTREME HEAT WARNING IS IN EFFECT MONDAY  
FOR THESE LOCALES.  
 
-A FEW THUNDERSTORMS THIS AFTERNOON MAINLY IN COCHISE COUNTY THEN  
DRIER CONDITIONS RETURN THIS WEEKEND WITH ONLY A SLIGHT CHANCE OF  
THUNDERSTORMS ALONG THE INT'L BORDER IN COCHISE COUNTY TOMORROW.  
 
-MONSOON 2025 WILL SWING INTO FULL GEAR NEXT WEEK. THE HEAT WILL BE  
ON THE DOWNWARD TREND BY MIDWEEK AS MOISTURE WILL BE ON THE  
INCREASE. INITIAL MONSOON STORM THREATS WILL BE FOCUSED MORE ON  
GUSTY WINDS, BUT WILL QUICKLY TRANSITION MORE TOWARDS HEAVY RAIN AND  
FLASH FLOODING THREATS AS THE WEEK PROGRESSES. THIS INCLUDES  
INDEPENDENCE DAY.  
   
DISCUSSION
 
DOPPLER RADAR THIS AFTERNOON SHOWED ISOLATED SHOWERS  
AND A FEW THUNDERSTORMS AGAIN THAT DEVELOPED EAST AND SOUTH OF  
TUCSON ACROSS HIGHER TERRAIN AREAS. ISOLATED SHOWER AND THUNDERSTORM  
ACTIVITY WILL CONTINUE THIS AFTERNOON WITH THE BEST CHANCES  
CONSOLIDATED ALONG AND NEAR THE AZ/NM AND INTERNATIONAL BORDER IN  
COCHISE, GRAHAM, GREENLEE, AND SANTA CRUZ COUNTIES.  
 
LOOKING AT THE UPPER PATTERN, HIGH PRESSURE IS GRADUALLY RETURNING  
TO THE DESERT SOUTHWEST WITH FURTHER AMPLIFICATION EXPECTED THIS  
WEEKEND. THE HIGHER PRESSURE BUILDING IN WILL GENERALLY RESULT IN  
WARMER, DRIER, AND SUBSIDING AIR ALOFT WITH DECREASING CHANCES FOR  
PRECIPITATION. A SLIGHT CHANCE (10-15%) FOR AN ISOLATED SHOWER OR  
THUNDERSTORM WILL REMAIN ALONG THE INTERNATIONAL BORDER IN COCHISE  
COUNTY TOMORROW AS WELL AS THE WHITE MOUNTAINS. HOWEVER, THE BEST  
CHANCES (15-30%) WILL REMAIN TO OUR EAST IN NEW MEXICO AND SOUTH IN  
SONORA MX.  
 
OTHERWISE, TEMPERATURES WILL BE ON THE RISE THIS WEEKEND AS A RESULT  
OF THE HIGH PRESSURE AND ARE EXPECTED TO PEAK ON MONDAY AFTERNOON.  
AN EXTREME HEAT WARNING IS IN EFFECT FOR MONDAY FOR THE DESERTS OF  
SE ARIZONA AND UPPER GILA RIVER VALLEY WITH HIGHS 108 TO 112  
DEGREES. EXPECT A BIT OF AN UPTICK IN THUNDERSTORM CHANCES MONDAY  
AFTERNOON AND EVENING, MAINLY FROM TUCSON EASTWARD. GUSTY OUTFLOW  
WINDS WOULD BE THE PRIMARY THREAT WHICH COULD ALSO RESULT IN REDUCED  
VISIBILITY FROM BLOWING DUST.  
 
AS THE REST OF NEXT WEEK PROGRESSES, A STEADY INCREASE IN MOISTURE  
FROM THE SOUTH AND EAST IS EXPECTED AS THE SUBTROPICAL HIGH  
POSITIONS ITSELF MORE TOWARDS THE FOUR CORNERS WITH TROUGHING NEAR  
THE SOUTHERN CALIFORNIA COAST. THIS SCENARIO WILL HELP USHER IN WELL  
ABOVE NORMAL MOISTURE BY MID TO LATE NEXT WEEK WITH A QUICK  
TRANSITION FROM OUR TYPICAL EARLY SEASON MONSOON THREATS INCLUDING  
GUSTY WINDS AND BLOWING DUST TO MORE OF A HEAVY RAIN/FLASH FLOOD  
THREAT WITH WIND POTENTIAL AS WELL BY AROUND NEXT THURSDAY AND  
INDEPENDENCE DAY. WITH THE INCREASED MOISTURE, TEMPERATURES WILL  
DROP BACK DOWN TO NEAR NORMAL BY WEDNESDAY AND THEN BELOW NORMAL  
LATE NEXT WEEK. LOOKS LIKE MONSOON 2025 MAY BE OFF TO AN ABRUPT  
START. STAY TUNED!  
 

 
   
AVIATION
 
VALID THROUGH 29/00Z.  
SCT TO BKN CLOUDS AT AROUND 10-13K FT AGL MAINLY ALONG THE INT'L  
BORDER FROM KOLS EASTWARD AND ALONG THE AZ/NM BORDER GRADUALLY  
DECREASING IN COVERAGE AFTER 28/07Z. FOR THESE AREAS, ISOLD  
-SHRA/TS DIMINISHING AFTER 28/03Z. ISOLD GUSTS UP TO 40 KTS NR  
-TSRA OTHERWISE WINDS LIGHT AND UNDER 12 KTS WITH AN OCNL AFTN GUST  
UP TO 20 KTS. OVERNIGHT, WINDS WILL REMAIN BELOW 8 KTS VRBL IN  
DIRECTION. TOMORROW AFTERNOON WINDS WILL BE NWLY REMAINING UNDER 12  
KTS WITH SCT CLOUDS AT AROUND 10-13K FT AGL. AVIATION DISCUSSION NOT  
UPDATED FOR TAF AMENDMENTS.  
 

 
   
FIRE WEATHER
 
ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON  
MAINLY ALONG THE AZ/NM BORDER AND INT'L BORDER FROM NOGALES  
EASTWARD. MINIMUM RELATIVE HUMIDITIES FROM 10 TO 20 PERCENT, WITH A  
DRYING AND WARMING TREND THIS WEEKEND. WINDS GENERALLY LIGHT AND  
UNDER 15 MPH WITH ISOLATED GUSTS UP TO 45 MPH UNDER ANY  
THUNDERSTORMS MOISTURE WILL BE ON THE RISE NEXT WEEK WITH WIDESPREAD  
RAIN CHANCES BY MID TO LATE NEXT WEEK. INITIALLY, THE MAIN THREATS  
WILL BE GUSTY WINDS EARLY IN THE WEEK, BUT THAT WILL TRANSITION TO  
BOTH A WIND AND RAIN/FLOODING THREAT LATE NEXT WEEK.  
 

 
   
TWC WATCHES/WARNINGS/ADVISORIES
 
 
EXTREME HEAT WARNING FROM 10 AM TO 8 PM MST MONDAY FOR AZZ501-502-  
504>506-509.  
 

 
 

 
 
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