694
FXUS65 KFGZ 081051
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
351 AM MST Tue Sep 8 2026

.SYNOPSIS...Storm activity will be confined to eastern Arizona
today before gradually spreading back westward through the week.
Widespread shower and thunderstorm activity could develop by
Friday and Saturday with a passing weather disturbance.
Temperatures warming to above normal today through Thursday, then
cooling off over the weekend.

&&

.DISCUSSION...High pressure aloft was centered over Oklahoma
early morning Tuesday with a strong trough centered over the
Pacific Northwest.

From Today into Thursday...High pressure will gradually build
back over Arizona in response to the Pacific Northwest trough
moving into the central United States. Monsoon moisture will
continue to linger and even gradually increase through this
period. As a result, the afternoon/evening shower and thunderstorm
threat will continue across the high terrain of eastern Arizona
but also gradually spread westward along the Mogollon Rim. Any
heavy rain potential is expected to remain confined to the White
Mountains region. Look for warmer temperatures as the high builds
with mountain temperatures climbing to the upper 70s to mid 80s
reaching 95 to 105 at lower elevations.

For Friday and beyond...An additional trough is expected to drive
across the Pacific Northwest pushing the high center to the east
of Arizona. It appears monsoon moisture will remain in play and
interact with the passing Pacific Northwest trough. The models
are showing good chances for widespread coverage of showers and
thunderstorms Friday through Saturday with some level of activity
continuing through the overnight hours. The passing trough will
result in increased vertical wind shear with a few storms possibly
becoming organized, thus raising the threat of severe
thunderstorms and localized flash flooding. The trough heads
eastward on Sunday with a drier and more stable air mass moving
across most of northern Arizona. Under the influence of the trough
it will be come breezy with general west to southwest winds at
10-20 mph gusting to 25 mph starting Friday and lasting through
the weekend.

&&

.AVIATION...Tuesday 08/12Z through Wednesday 09/12Z...Primarily
VFR conditions. Brief MVFR conditions possible in isolated to scattered
SHRA/TSRA between 19Z-03Z, mainly south of the I-40 corridor.
Winds W to NW 5-15 kts between 18Z-03Z. Otherwise, winds light and
variable.

OUTLOOK...Wednesday 09/12Z through Friday 11/12Z...Mainly VFR
conditions, brief MVFR conditions possible with thunderstorms.
Scattered SHRA/TSRA over the Mogollon Rim and White Mountains on
Wednesday, isolated elsewhere. Storm coverage increases and
spreads westward on Thursday and Friday. Winds variable 5-10 kts
on Wednesday, turning W to NW 5-15 kts on Thursday, then
increasing and becoming SW to W at 10-20 kts gusting to 20 kts
Friday.

&&

.FIRE WEATHER...Today and Wednesday...Expect low grade monsoon
activity with afternoon shower and thunderstorm chances confined to
the Mogollon Rim and the mountains of eastern Arizona. Winds south
to southwest 5-15 mph with gusts to around 20 mph each afternoon,
then light and variable or terrain driven overnight. Turning warmer
with minimum RH ranging from 15% across the lower elevations of
northeast Arizona to 30-40% in the mountains.

Thursday through Saturday...Low to medium grade monsoon activity
developing. On thursday, shower and thunderstorm chances remain
confined to the Rim and White Mountains. By Friday and Saturday,
with a passing weather, disturbance wider coverage of showers and
storms is anticipated. Daytime winds south to southwest 5-15 mph on
Thursday then strengthening to 10-20 mph gusting to 25-30 mph on
Friday and Saturday. Winds remaining locally gusty at night.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

PUBLIC...McCollum
AVIATION...McCollum
FIRE WEATHER...McCollum

For Northern Arizona weather information visit
weather.gov/flagstaff