865
FXUS65 KFGZ 032340
AFDFGZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
440 PM MST THU SEP 3 2026
SYNOPSIS
DRIER WEATHER CONTINUES TODAY, WITH ISOLATED SHOWERS
AND THUNDERSTORMS POSSIBLE, MAINLY NEAR THE WHITE MOUNTAINS. THERE
WILL BE A GRADUAL INCREASE IN COVERAGE FRIDAY INTO THE WEEKEND, AS
MOISTURE STARTS TO PUSH NORTHWARD. EXPECT BREEZY SOUTHWEST WINDS TO
START EASING THIS WEEKEND, ALONG WITH SLIGHTLY BELOW NORMAL
TEMPERATURES CONTINUING INTO EARLY NEXT WEEK.
DISCUSSION
RADAR AND SATELLITE IMAGERY SHOWS A FEW LIGHT
SHOWERS NEAR THE WHITE MOUNTAINS IN PORTIONS OF EASTERN GILA
COUNTY EARLY THIS AFTERNOON, WITH ADDITIONAL SHOWERS AND
THUNDERSTORMS DEVELOPING FURTHER SOUTH IN SOUTHEASTERN AZ.
OTHERWISE, BREEZY SOUTHWEST WINDS WITH GUSTS UP TO 35 MPH,
ESPECIALLY IN WESTERN ARIZONA, AND DRY PATTERN EXTENDS ACROSS
NORTHERN AZ AS THE TROUGH CONTINUES TO BE CENTERED OVER THE
PACIFIC NORTHWEST. HI-RES MODELS STILL TO SHOW THE POTENTIAL FOR
OVERNIGHT CONVECTION TONIGHT INTO EARLY FRIDAY MORNING IN GILA,
SOUTHERN AND CENTRAL APACHE AND NAVAJO, AND SOUTHEASTERN YAVAPAI
COUNTIES, BUT THIS WILL BE HIGHLY DEPENDENT ON HOW SHOWERS AND
THUNDERSTORMS ACTIVITY DEVELOPS IN SOUTHEASTERN AZ, SO THE CHANCE
FOR SHOWERS FOR SHOWERS AND THUNDERSTORMS FOR MOST AREAS WERE KEPT
AROUND 40% OR LESS.
STILL EXPECTING A GRADUAL INCREASE IN SHOWER AND THUNDERSTORM
COVERAGE FRIDAY AND INTO THE WEEKEND AS MOISTURE ASSOCIATED WITH
HURRICANE MARIE IS SIPHONED BY THE LARGE TROUGH AND LIFTED
NORTHEASTWARD TOWARD NORTHWESTERN AZ, AND A STRENGTHENING OF THE
RIDGE IN THE CENTRAL US CONTINUES TO SUPPORT SOUTHERLY FLOW IN
SOUTHEAST AZ AND PUSHING MOISTURE NORTHWARD INTO EASTERN AZ. THE
BIGGEST CHALLENGES HOWEVER, ARE: 1) TIMING OF THIS MOISTURE BEING
SIPHONED AND BEING PUSHED INTO AZ. 2) HOW MUCH MOISTURE WILL BE
SIPHONED AND WHERE THE GREATEST CONCENTRATION WILL SET UP. 3) WHAT
KIND SYNOPTIC PROFILE WILL BE IN PLACE. FOR THE MOISTURE, MODELS
SHOW A GRADUAL INCREASE IN MOISTURE FRIDAY AND SATURDAY AND HAVE
DELAYED THE BULK OF THE MOISTURE TO SUNDAY AND HAVE SHIFTED IT
NORTHEASTWARD INTO NV, UT, AND FAR NW AZ. THIS IS BASED ON
MARIE'S CURRENT TRACK AND SPEED AND WHEN THE PEAK INTERACTION
BETWEEN MARIE AND THE TROUGH WILL OCCUR. FOR HOW MUCH MOISTURE, A
PWAT AROUND 0.92 INCHES IS THE 90TH PERCENTILE OF PWAT VALUES FOR
FLAGSTAFF THIS TIME OF YEAR AND THE NBM SHOWS A 30-40% CHANCE
EXCEEDING THIS PWAT VALUE BY SATURDAY AND A 50-65% CHANCE SUNDAY,
THEN DECREASING TO AROUND 40-50% BY MONDAY EVENING. FOR THE
SYNOPTIC PROFILE, FORECAST ENSEMBLES HAVE A THE STRONGEST 500 MB
WINDS SETTING UP OVER NV AND UT, WITH 25-35 KTS WINDS OVER NW AZ
AND DECREASING TO 15-25 KTS OVER EASTERN AZ AS THE LARGE TROUGH
MOVES NORTHEAST ACROSS THE PACIFIC NW. THE PLACEMENT OF THE
MOISTURE AND SYNOPTIC PATTERN CURRENTLY PLACES THE GREATEST RISK
FOR STORMS AND FLOODING SOMEWHERE AROUND OR NORTH OF THE NV, UT,
AZ BORDER, BUT THIS PATTERN MAY SHIFT OVER THE NEXT FEW DAYS, AND
DOES NOT MEAN SHOWERS AND THUNDERSTORMS WILL NOT DEVELOP ACROSS
CENTRAL OR EASTERN AZ AS DIRNUAL-MONSOONAL SHOWERS AND
THUNDERSTORMS ALONG THE HIGHER TERRAIN ARE POSSIBLE, ESPECIALLY
IF THE TROPICAL MOISTURE DOES NOT CREATE A MID OR UPPER-LEVEL
CLOUD DECK OVER THE STATE DURING THE DAYTIME HOURS. FOR NOW, THE
GREATEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS ON SUNDAY WILL BE
NEAR AND NORTH OF THE KAIBAB PLATEAU AND THE WHITE MOUNTAINS,
WITH DAY TIME TEMPERATURES STAYING NEAR OR SLIGHTLY BELOW NORMAL
INTO EARLY NEXT WEEK.
AVIATION...FRIDAY 04/00Z THROUGH SATURDAY 05/00Z
EXPECT MAINLY
VFR CONDITIONS. ISOLD-SCT SHRA/TSRA EAST OF A KPAN-KRQE LINE, ISOLD
OR NO CELLS ELSEWHERE. SOME NOCTURNAL ACTIVITY MAY FORM THIS EVENING
AND OVERNIGHT FROM THE I-17 CORRIDOR UP TO THE FOUR CORNERS, BUT
CONFIDENCE IS LOW. DAYTIME SFC WINDS SW15-25G30KTS.
OUTLOOK...SATURDAY 05/00Z THROUGH MONDAY 07/00Z...EXPECT MAINLY VFR
CONDITIONS. SCT ACTIVITY CONTINUES MAINLY FOR THE EASTERN PORTIONS
FOR EARLY FRIDAY EVENING, POSSIBLY BECOMING MORE WIDESPREAD HEADING
INTO SATURDAY AND SUNDAY. DAYTIME SFC WINDS ARE NOT ANTICIPATED TO
AFFECT FLIGHT OPERATIONS OVER THE WEEKEND.
FIRE WEATHER...FRIDAY AND SATURDAY
FRIDAY WILL SEE GENERALLY DRY
AND BREEZY CONDITIONS WEST OF A SHOW LOW TO FOUR CORNER LINE WITH
SCATTERED SHOWERS AND THUNDERSTORMS ALONG AND EAST OF THIS LINE. ON
SATURDAY, ISOLATED TO SCATTERED ACTIVITY SPREADS AREA WIDE. WINDS
SOUTHWEST 10-20 MPH WITH GUSTS UP TO 35 MPH, STRONGEST ACROSS
NORTHWEST ARIZONA. LITTLE CHANGE IN TEMPERATURES.
SUNDAY THROUGH TUESDAY...INCREASING MOISTURE WILL CAUSE SHOWER AND
THUNDERSTORM COVERAGE TO EXPAND. HIGHEST CHANCES FOR RAINFALL WILL
BE SEEN ON SUNDAY. WINDS SOUTH THROUGH SOUTHWEST 5-15 MPH EACH DAY,
THEN GENERALLY LIGHT AND VARIABLE OVERNIGHT. LITTLE CHANGE IN
TEMPERATURES.
FGZ WATCHES/WARNINGS/ADVISORIES
NONE.
PUBLIC...SCHANK
AVIATION...PETERSON
FIRE WEATHER...MCCOLLUM
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
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