031
FXUS65 KFGZ 111754
AFDFGZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1054 AM MST THU SEP 11 2025
SYNOPSIS
WINDY CONDITIONS ARE EXPECTED THROUGH FRIDAY, WITH
GRADUALLY COOLER TEMPERATURES THROUGH THE WEEKEND. SCATTERED SHOWERS
AND THUNDERSTORMS ARE FORECAST THIS AFTERNOON THROUGH FRIDAY,
MAINLY ACROSS EASTERN ARIZONA. DRY CONDITIONS RETURN BY THE
WEEKEND.
DISCUSSION
A FAIRLY STRONG CLOSED LOW FOR THIS TIME OF YEAR WAS
CENTERED OVER NORTHERN CALIFORNIA THIS MORNING. INCREASING
PRESSURE GRADIENTS WELL AHEAD OF THE LOW BROUGHT WINDY CONDITIONS
ON WEDNESDAY TO OUR REGION, WITH GUSTS IN THE 35-50 MPH RANGE. AS
THE LOW MOVES SLOWLY EASTWARD OVER THE NEXT COUPLE OF DAYS, THE
WINDY CONDITIONS WILL PERSIST WITH AFTERNOON GUSTS MOSTLY IN THE
30-40 MPH RANGE. DAYTIME TEMPERATURES WILL BE A COUPLE DEGREES
COOLER TODAY THROUGH SATURDAY AS WELL. WITH THE INCREASED SOUTH-
SOUTHWEST FLOW ALOFT, DEEPER MOISTURE LOCATED OVER SONORA IS BEING
PULLED NORTHWARD INTO EASTERN ARIZONA. THIS WILL PERSIST THROUGH
FRIDAY EVENING, WITH THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS
EAST OF A HEBER TO KAYENTA LINE AFFECTING APACHE AND PORTIONS OF
NAVAJO COUNTIES. FARTHER WEST, A FEW SHOWERS OR STORMS CAN'T BE
RULED OUT, BUT CHANCES ARE ONLY 10-20%. IN APACHE COUNTY, STORM
CHANCES ARE 30-50% THIS AFTERNOON AND OVERNIGHT, INCREASING TO
50-70% ON FRIDAY. WITH DEEP LAYER WIND SHEAR PRESENT DUE TO THE
APPROACHING LOW, AND INCREASED INSTABILITY IN THE MOISTURE PLUME,
THERE IS A CHANCE OF A FEW STRONG TO SEVERE THUNDERSTORMS PRIMARILY
IN APACHE COUNTY AND SOUTHERN NAVAJO COUNTY. THE MOST FAVORABLE
TIMING FOR THE STRONGER STORMS APPEARS TO BE ON FRIDAY AS DAYTIME
HEATING INCREASES INSTABILITY, THOUGH THERE IS A LOWER CHANCE EVEN
THURSDAY NIGHT IF STORMS MANAGE TO DEVELOP. BOTH DAMAGING WINDS
AND LARGE HAIL (1" OR GREATER DIAMETER) WILL BE POSSIBLE IN
ISOLATED STORMS, AND THE SPC HAS PLACED THIS AREA IN A MARGINAL
RISK FOR SEVERE WEATHER.
BY THE WEEKEND - MUCH DRIER AIR IS FORECAST TO SWEEP EASTWARD AS
THE LOW ADVANCES INTO OUR REGION, ENDING THE CHANCE OF STORMS.
THIS WILL ALSO CAUSE SOUTHWEST WINDS TO DIMINISH TO 10-20 MPH.
SATURDAY IS CURRENTLY FORECAST TO BE THE COOLEST DAY OF THE
FORECAST PERIOD, WITH HIGHS AROUND 5 DEGREES BELOW NORMAL. WITH
THE DRIER AIR AND LIGHTER WINDS, OVERNIGHT LOWS WILL BE THE
COOLEST WE HAVE SEEN IN SOME TIME, LIKELY INTO THE 30S SUNDAY AND
MONDAY MORNINGS FOR MANY LOCATIONS ABOVE 6500 FEET. THE USUAL COLD
POCKETS (BELLEMONT, TUSAYAN, WINDOW ROCK) MAY APPROACH THE
FREEZING MARK. SEASONABLE TEMPERATURES ARE FORECAST TO RETURN NEXT
WEEK, WITH SOME INDICATIONS THAT ANOTHER MOISTURE PLUME WILL MOVE
NORTHWARD INTO THE STATE AND BRING A CHANCE OF SHOWERS AND STORMS
BACK TO THE AREA. STILL QUITE A BIT OF UNCERTAINTY IN THIS
SCENARIO, SO PRECIP CHANCES ARE ONLY IN THE 10-20% RANGE FOR NOW, AND
MAINLY FOR THE EASTERN HALF OF THE STATE.
AVIATION...THURSDAY 11/18Z THROUGH FRIDAY 12/18Z
MAINLY VFR
CONDITIONS. ISOLATED TO SCATTERED SHRA/TSRA AFTER 19-20Z,
PRIMARILY EAST OF A KPAN-KINW-K0V7 LINE. ACTIVITY MAY CONTINUE
OVERNIGHT WITH THE HIGHEST COVERAGE IN APACHE COUNTY.
BRIEF/LOCALIZED MVFR IN STRONGER STORMS WITH ERRATIC WINDS
GUSTING UP TO 40 KTS AND HAIL. WINDS ARE S-SW 15-20 KTS WITH GUSTS
30-35 KTS, DECREASING TO 15 KTS OR LESS AFTER 02Z.
OUTLOOK...FRIDAY 12/18Z THROUGH SUNDAY 14/18Z...MAINLY VFR
CONDITIONS EXPECTED. ISOLATED TO SCATTERED -SHRA/-TSRA POSSIBLE
PRIMARILY EAST OF A KPAN-KINW-K0V7 BETWEEN 18Z-02Z EACH DAY.
WINDS ARE SW 15-20KTS WITH GUSTS TO 35KTS ON FRIDAY, BECOMING S-SW
5-10 KTS OVERNIGHT. WINDS ARE SW-W 10-15KTS ON SATURDAY, THEN
LIGHT AND VRB OVERNIGHT.
FIRE WEATHER...TODAY AND FRIDAY
SLIGHTLY COOLER AND WINDY.
SOUTHWEST WINDS FROM 15 TO 25 MPH, WITH GUSTS FROM 30 TO 40 MPH EACH
DAY, FROM LATE MORNING THROUGH EARLY EVENING. SOME MOISTURE BEING
PULLED INTO EASTERN ARIZONA WILL ALSO ALLOW FOR DAILY SHOWERS AND
THUNDERSTORMS, SOME STORMS COULD BE STRONG. STORMS WILL LARGELY BE
CONFINED TO APACHE AND NAVAJO COUNTIES.
SATURDAY THROUGH MONDAY...CONDITIONS WILL RAPIDLY DRY FROM WEST TO
EAST, WITH MINIMUM RELATIVE HUMIDITY VALUES MAINLY IN THE TEENS
THROUGH THE PERIOD. SEASONABLE DAYTIME TEMPERATURES. DAYTIME
SOUTH THROUGH SOUTHWEST WINDS 10 TO 20 MPH.
FGZ WATCHES/WARNINGS/ADVISORIES
NONE.
PUBLIC...JJ/LEWANDOWSKI
AVIATION...JJ
FIRE WEATHER...JJ
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
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