828  
FXUS65 KTWC 170836  
AFDTWC  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TUCSON AZ  
136 AM MST FRI OCT 17 2025  
   
SYNOPSIS
 
BELOW NORMAL TEMPERATURES PREVAIL THE NEXT COUPLE OF  
DAYS THEN TEMPERATURES WARM TO NEAR NORMAL SUNDAY INTO EARLY NEXT  
WEEK. DRY CONDITIONS WILL ALSO PREVAIL THROUGH THE MIDDLE OF NEXT  
WEEK.  
 

 
   
DISCUSSION
 
TROUGHING WILL PERSIST OVER THE NEXT COUPLE OF DAYS  
WITH A WEAK SHORTWAVE MOVING THROUGH ARIZONA TODAY. THIS COULD  
LEAD TO SLIGHTLY ELEVATED WINDS IN COCHISE COUNTY, BUT THE  
STRONGEST WINDS WILL BE EAST IN NEW MEXICO. THIS WILL KEEP  
TEMPERATURES 5-8 DEGREES BELOW NORMAL THROUGH SATURDAY.  
THEREAFTER THE UPPER AIR PATTERN CHANGES WITH A CUTOFF LOW  
CENTERED OFF THE NORTHERN COAST OF BAJA AND HIGH PRESSURE BUILDING  
INTO NORTHERN MEXICO AND TEXAS. THIS WILL LEAD TO SHORTWAVE  
RIDGING OVER ARIZONA. THE CLOSED LOW REMAINS OFFSHORE THROUGH AT  
LEAST TUESDAY. THANKS TO THE RIDGE TEMPERATURES WILL WARM BECOMING  
AROUND NORMAL TO A FEW DEGREES ABOVE NORMAL SUNDAY INTO THE MIDDLE  
OF THE WEEK. TUCSON WILL BE FLIRTING WITH 90 DEGREES MONDAY AND  
TUESDAY WITH NBM PROBABILITIES FOR 90 OR ABOVE 25 AND 50 PERCENT  
RESPECTIVELY.  
 
TUESDAY INTO WEDNESDAY THE CUTOFF LOW BEGINS TO OPEN UP AND MOVES  
ON SHORE. MODELS DO SHOW A MODEST INCREASE IN MOISTURE AS THE LOW  
MOVES INLAND WITH PWAT VALUES UP TO 175 PERCENT OF NORMAL EAST OF  
TUCSON BY WEDNESDAY. RIGHT NOW THE TROUGH TRACKS THROUGH NORTHERN  
ARIZONA PUTTING THE BEST RAIN CHANCES TO THE NORTH WITH SLIGHT  
CHANCES FOR NORTHERN GRAHAM AND GREENLEE COUNTIES. STILL COME  
UNCERTAINTY WITH THE EXACT TRACK OF THE LOW, SO A FURTHER SOUTH  
TRAJECTORY COULD INCREASE RAIN CHANCES FOR SOUTHEAST ARIZONA. THE  
TROUGH WILL ALSO BRING A SLIGHTLY COOLER AIR MASS WITH HIGH  
TEMPERATURES BECOMING A FEW DEGREES BELOW NORMAL WEDNESDAY AND  
THURSDAY.  
 

 
   
AVIATION
 
VALID THROUGH 18/12Z.  
FEW-SCT CUMULUS CLOUDS AT 4K-8K FT THIS AFTERNOON AND EVENING, SKC  
OTHERWISE. SFC WINDS NW/W AT 6-12 KTS, WITH THE STRONGEST WINDS  
KTUS EASTWARD LATE THIS MORNING INTO THE EVENING. AT OTHER TIMES  
WINDS WILL BE TERRAIN DRIVEN AND REMAIN UNDER 10 KTS. AVIATION  
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.  
 

 
   
FIRE WEATHER
 
MINIMUM RH VALUES WILL BE IN THE 15-30 PERCENT  
RANGE IN THE VALLEYS INTO NEXT WEEK. 20-FOOT WINDS MAINLY 15 MPH  
OR LESS, WITH OCCASIONAL GUSTS TO 20-25 MPH. HIGH TEMPERATURES  
WILL BE BELOW NORMAL THROUGH SATURDAY, WARMING TO NORMAL OR JUST  
ABOVE NORMAL LEVELS SUNDAY INTO NEXT WEEK. THE NEXT CHANCE OF  
PRECIPITATION WILL BE AROUND NEXT TUESDAY/WEDNESDAY WITH A SLIGHT  
(~20%) CHANCE OF SHOWERS IN NORTHERN GRAHAM AND GREENLEE COUNTIES.  
 

 
   
TWC WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
HARDIN  
 
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab AZ Page Main Text Page