186
FXUS65 KFGZ 060529
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1029 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...Sunday 06/06Z through Monday 07/06Z...Expect mainly VFR
conditions. Mainly BKN-OVC CIGS 10-12kft AGL overnight. ISOLD-SCT
SHRA/-TSRA again AFT 18Z-20Z Sunday, activity is most likely over
southern Apache County as well as west of a KCMR-KPGA line. Mainly
daytime sfc winds SW-W10-20kts.

OUTLOOK...Monday 07/06Z through Wednesday 09/06Z...Expect mainly VFR
conditions. SCT SHRA/-TSRA each day, but mainly over southern Navajo
and Apache counties. Daytime sfc winds are not anticipated to affect
flight operations.

&&

.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...Peterson
FIRE WEATHER...Bernhart

For Northern Arizona weather information visit
weather.gov/flagstaff