814
FXUS65 KFGZ 152117
AFDFGZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
217 PM MST FRI AUG 15 2025
SYNOPSIS
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO
THIS EVENING, BECOMING MAINLY ISOLATED FROM SATURDAY INTO EARLY
NEXT WEEK AS DRIER AIR MOVES ACROSS THE AREA. HIGH PRESSURE WILL
GRADUALLY BUILD AND AS A RESULT WARMER TEMPERATURES ARE ON THE
WAY, LIKELY CLIMBING TO WELL ABOVE NORMAL BY MONDAY OR TUESDAY OF
NEXT WEEK.
DISCUSSION
THE COMPLICATED INTERACTION BETWEEN A TROUGH ALONG
THE WEST COAST, HIGH PRESSURE CENTERED OVER OKLAHOMA/KANSAS AND
MONSOON MOISTURE WILL CONTINUE TO DELIVER CHANCES FOR SHOWERS AND
THUNDERSTORMS THROUGH TONIGHT. ACTIVITY WILL TEND TOWARD SCATTERED
ALONG AND SOUTH OF A GRAND CANYON-FLAGSTAFF-SHOW LOW LINE, WITH
GRADUALLY DIMINISHING STRENGTH AND COVERAGE THROUGH THE NIGHT.
NORTH OF THIS LINE LOOK FOR MAINLY ISOLATED ACTIVITY ENDING BY
LATE EVENING.
FOR SATURDAY AND SUNDAY...THE WEST COAST TROUGH WINS THE BATTLE
FOR A WHILE. LOOK FOR A DRIER AIR MASS TO OVERTAKE MOST OF
NORTHERN ARIZONA. MOST LOCATIONS WILL SEE ONLY ISOLATED AFTERNOON
AND EVENING SHOWERS AS LIMITED MOISTURE LINGERS. FURTHER EAST,
MAINLY THE WHITE MOUNTAINS AND FAR EASTERN LITTLE COLORADO RIVER
VALLEY AFTERNOON/EVENING SHOWERS AND STORMS WILL REMAIN MORE
SCATTERED WHERE THE EDGE OF THE MONSOON MOISTURE PLUME HANGS ON.
WITH FEWER CLOUDS AND A DRIER AIR MASS MOST LOCATIONS WILL SEE THE
BEGINNING OF A WARMING TREND. LOOK FOR WEST SOUTHWEST WINDS AT 5
TO 15 MPH BECOMING LOCALLY GUSTY WITH DAYTIME HEATING AND TERRAIN
EFFECTS.
ON MONDAY AND TUESDAY...HIGH PRESSURE WILL BEGIN TO BUILD ACROSS
ARIZONA FROM THE EAST. THE AIR MASS WILL REMAIN ON THE DRY SIDE
ALONG WITH A LIKELY MID-LEVEL WARM/CAPPING LAYER ASSOCIATED WITH
THE BUILDING HIGH. AS A RESULT, THE SCATTERED SHOWER AND
THUNDERSTORM THREAT WILL REMAIN CONFINED TO THE WHITE MOUNTAINS
REGION, ISOLATED ELSEWHERE. IN ADDITION, DAYTIME TEMPERATURES
CLIMBING TO WELL ABOVE NORMAL. WE'RE LOOKING AT MID TO UPPER 80S
IN THE MOUNTAINS, UPPER 90S AT LOCATIONS SUCH AS PRESCOTT, PAYSON,
WINSLOW AND CHINLE AND AROUND 110 AT OUR LOWEST ELEVATIONS.
FROM WEDNESDAY ONWARD...STRONG HIGH PRESSURE GRADUALLY HEADS
WESTWARD STRADDLING NORTHERN ARIZONA AND THE GREAT BASIN.
AT THE SAME TIME, THUNDERSTORM COMPLEX ACTIVITY WILL RAMP UP OVER
NORTHWEST MEXICO SENDING OUTFLOW/GULF OF CALIFORNIA MOISTURE
SURGES INTO ARIZONA. AS A RESULT, WE'RE LOOKING AT A GRADUAL
INCREASE IN MOISTURE AND THUNDERSTORM ACTIVITY WITH AT LEAST LOW
GRADE MONSOON ACTIVITY ANTICIPATED. HOT TEMPERATURES WILL
CONTINUE.
AVIATION...FRIDAY 15/18Z THROUGH SATURDAY 16/18Z
MAINLY VFR
EXPECTED. SCATTERED SHRA/TSRA THROUGH THE TAF PERIOD WITH BRIEF
MVFR AND GUSTY, ERRATIC WINDS UP TO 40 KTS POSSIBLE IN AND AROUND
TS. OUTSIDE OF STORMS, EXPECT SW THROUGH NW WINDS 10-15 KTS WITH
GUSTS 20-25 KTS WITH LIGHT AND VARIABLE WINDS DEVELOPING OVERNIGHT.
OUTLOOK...SATURDAY 16/18Z THROUGH MONDAY 18/18Z...MAINLY VFR
EXPECTED. ISOLATED TO SCATTERED -SHRA/-TSRA SATURDAY, DECREASING
TO ISOLATED AND MAINLY OVER THE HIGHER TERRAIN ON SUNDAY. BRIEF
MVFR CONDITIONS AND GUSTY, ERRATIC WINDS POSSIBLE IN AND AROUND
TS. OUTSIDE OF STORMS, SW THROUGH W WINDS 5-15 KTS EACH DAY WITH
LIGHT AND VARIABLE WINDS OVERNIGHT.
FIRE WEATHER...SATURDAY AND SUNDAY
DRIER AIR WILL MOVE IN.
LOOK FOR ISOLATED SHOWERS AND THUNDERSTORMS FOR MUCH OF NORTHERN
ARIZONA, BUT REMAINING SCATTERED ACROSS THE WHITE MOUNTAINS
REGION. EXPECT GUSTY AND ERRATIC WINDS IN AND AROUND ANY STORMS.
OUTSIDE OF STORMS, DAYTIME WINDS WEST-SOUTHWEST 5-15 MPH WITH
TERRAIN DRIVEN WINDS EACH NIGHT. A WARMING TREND WILL BEGIN.
MONDAY THROUGH WEDNESDAY...HOT AND MAINLY DRY. EXPECT ISOLATED
SHOWERS AND THUNDERSTORMS EACH DAY, PRIMARILY OVER THE EASTERN
MOGOLLON RIM AND WHITE MOUNTAINS. MINIMUM AFTERNOON RH VALUES 10-20%
MOST AREAS, HIGHER IN THE WHITE MOUNTAINS REGION. GUSTY AND ERRATIC
OUTFLOW WINDS POSSIBLE IN AND AROUND THUNDERSTORMS. OUTSIDE OF
STORMS, DAYTIME WINDS SOUTHWESTERLY 5-15 MPH EACH AFTERNOON WITH
TERRAIN DRIVEN WINDS AT NIGHT.
FGZ WATCHES/WARNINGS/ADVISORIES
FLOOD WATCH UNTIL 8 PM MST /9 PM MDT/ THIS EVENING FOR
AZZ004>006.
PUBLIC...MCCOLLUM
AVIATION...MCT
FIRE WEATHER...MCT
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
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