004
FXUS65 KFGZ 051937
AFDFGZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1237 PM MST SAT SEP 5 2026
SYNOPSIS
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS
WEEKEND, WITH SCATTERED ACTIVITY BY SUNDAY IN NORTHWEST ARIZONA
AND THE WHITE MOUNTAINS. STORM ACTIVITY WILL BE CONFINED TO FAR
EASTERN ARIZONA MONDAY BEFORE SPREADING BACK WESTWARD THROUGH NEXT
WEEK. TEMPERATURES WILL BE CLOSE TO NORMAL.
DISCUSSION
A LARGE UPPER LOW OVER THE NORTHWEST UNITED STATES
WILL LINGER THROUGH THE WEEKEND, WITH RIDGING TO OUR EAST. THIS
SETUP KEEPS SOUTH-SOUTHWESTERLY FLOW OVER OUR REGION WHICH WILL
ALLOW FOR AN INCREASE IN MOISTURE TONIGHT THROUGH SUNDAY. WHILE
PRECIPITABLE WATER VALUES WILL INCREASE ABOVE NORMAL FOR EARLY
SEPTEMBER, INSTABILITY DOES NOT LOOK HIGH AS MUCH OF THE MOISTURE
IS IN THE MID/UPPER LEVELS BRINGING CLOUDS AND LIMITING SURFACE
HEATING. SOME OF THIS MOISTURE, ESPECIALLY BY SUNDAY IN NORTHWEST
AZ, IS GETTING PULLED NORTHWARD FROM HURRICANE MARIE LOCATED
AROUND 700 MILES WEST OF THE TIP OF THE BAJA PENINSULA. FOR THE
REST OF TODAY, MAINLY JUST ISOLATED SHOWERS OR THUNDERSTORMS ARE
EXPECTED, WITH THE VAST MAJORITY OF LOCATIONS REMAINING DRY. LATER
TONIGHT THROUGH SUNDAY, THE DEEPER MOISTURE WILL MOVE INTO
NORTHWEST ARIZONA AND PORTIONS OF NV/UT, ALTHOUGH INSTABILITY IS
LACKING AND MUCH OF THE ACTIVITY MAY JUST BE LIGHT TO MODERATE
SHOWERS. THE MAIN BAND OF PRECIPITATION HAS ALSO CONTINUED TO
TREND FARTHER WESTWARD AND IS NOW FORECAST BY MUCH OF THE GUIDANCE
TO BE FROM SOUTHERN CA TO LAS VEGAS AND INTO UT. THERE IS MODERATE
CONFIDENCE THAT THIS AREA JUST BRUSHES FAR NORTHWEST COCONINO
COUNTY WHERE THERE IS AROUND A 40% CHANCE OF RAIN SUNDAY.
MONDAY - THE NORTHWEST US LOW IS FORECAST TO SHIFT EASTWARD
ALLOWING FOR SOME SIGNIFICANTLY DRIER AIR TO MOVE INTO OUR AREA
FROM THE WEST. STORM CHANCES WILL BE LIMITED TO AREAS ALONG THE
AZ/NM LINE WITH DRY WEATHER ELSEWHERE. STARTING TUESDAY AND
CONTINUING THROUGH NEXT WEEK - AN ELONGATED RIDGE COVERING MOST OF
THE SOUTHERN US WILL GRADUALLY SHIFT WESTWARD. THE FLOW AROUND
THIS RIDGE LOOKS FAVORABLE FOR MONSOON MOISTURE TO SHIFT BACK INTO
OUR REGION. STORM CHANCES INCREASE TO 30-50% EACH AFTERNOON FROM
WEDNESDAY ONWARD, HIGHEST FOR THE MOUNTAINS. TEMPERATURES SHOULD
BE SLIGHTLY WARMER THAN NORMAL FOR EARLY SEPTEMBER.
AVIATION...SATURDAY 05/18Z THROUGH SUNDAY 06/18Z
VFR
CONDITIONS EXPECTED. ONLY A FEW ISOLATED THUNDERSTORMS EXPECTED
OVER THE WHITE MOUNTAINS TODAY FROM 18Z-00Z. A BAND OF LIGHT RAIN
MOVES INTO NORTHWEST ARIZONA AFTER 09Z SUNDAY EXTENDING AS FAR
EAST AS THE GRAND CANYON REGION WITH DRY CONDITIONS ELSEWHERE.
WINDS S-SW 10-20KTS DAYTIME, LIGHT AND VARIABLE OR TERRAIN DRIVEN
OVERNIGHT.
OUTLOOK...SUNDAY 06/18Z THROUGH TUESDAY 08/18Z...MAINLY VFR
CONDITIONS, BRIEF MVFR POSSIBLE UNDER HEAVIER THUNDERSTORMS. SOME
SCATTERED SHOWERS/STORMS SUNDAY OVER NORTHWESTERN ARIZONA
THROUGHOUT THE DAY, WITH A FEW ISOLATED AFTERNOON THUNDERSTORMS
OVER THE RIM AND WHITE MOUNTAINS. SOME ISOLATED AFTERNOON
THUNDERSTORMS OVER THE EASTERN THIRD OF ARIZONA MONDAY WITH THE
REST OF THE STATE BEING DRY. WINDS SW-W 5-15KTS DAYTIME, LIGHT AND
VARIABLE OR TERRAIN DRIVEN OVERNIGHT.
FIRE WEATHER...SUNDAY AND MONDAY
A BAND OF MOISTURE FROM
HURRICANE MARIE WILL BRING SOME SHOWERS AND THUNDERSTORMS IN
NORTHWESTERN ARIZONA INCLUDING THE GRAND CANYON REGION. A FEW
ISOLATED AFTERNOON THUNDERSTORMS ARE POSSIBLE IN THE RIM AND WHITE
MOUNTAINS ON SUNDAY AS WELL, OTHERWISE THE REST OF THE REGION
REMAINS DRY. ON MONDAY THE EASTERN THIRD OF ARIZONA WILL SEE A FEW
ISOLATED AFTERNOON SHOWERS AND THUNDERSTORMS. HIGH TEMPERATURES
NEAR NORMAL TO FIVE DEGREES ABOVE NORMAL. WINDS S-SW 5-15 MPH WITH
GUSTS TO 25 MPH EACH AFTERNOON.
TUESDAY THROUGH THURSDAY...HIGH PRESSURE BUILDS IN FROM THE EAST
WITH INCREASING MOISTURE AND MONSOON ACTIVITY TUESDAY THROUGH
THURSDAY ACROSS NORTHERN ARIZONA. TEMPERATURES WARMING TO 5-10
DEGREES ABOVE AVERAGE. WINDS S-SW 5-15 MPH EACH DAY, LIGHT AND
VARIABLE OVERNIGHT.
FGZ WATCHES/WARNINGS/ADVISORIES
NONE.
PUBLIC...ZANKER
AVIATION...BERNHART
FIRE WEATHER...BERNHART
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page