Area Forecast Discussion
Issued by NWS Flagstaff, AZ

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769
FXUS65 KFGZ 281843
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1143 AM MST Mon Sep 28 2026

.SYNOPSIS...Widespread rain and cool temperatures will continue
today, with periods of moderate to heavy rainfall possible.
Widespread showers, along with increased thunderstorm activity,
continue Tuesday, bringing a heightened risk of flooding. A Flood
Watch remains in effect for northern Arizona through Tuesday
evening. Chances for showers and thunderstorms continue across
eastern Arizona on Wednesday, before warmer and drier weather
returns Thursday and Friday.

&&

.DISCUSSION...Current satellite imagery show a plume of moisture
originating from the remnants of Odalys moving across northern
Arizona. Meanwhile, Hurricane Polo is centered of the west coast
of Southern Baja California. Moisture associated with these two
features will interact with a closed low approaching northern
Arizona, which is currently centered over Central California. This
active weather pattern is forecast to bring a period of impactful
weather to the area through Wednesday.

Radar imagery shows a band of primarily stratiform precipitation
draped across northern Arizona from the southwest to northeast.
Rain rates are mostly light, with some embedded showers producing
moderate rainfall rates. With the cool and cloudy conditions, we
are not expecting robust storm development today, but some
isolated storm activity cannot be ruled out this afternoon. The
main concern is for flooding in areas that receive prolonged
periods of moderate to heavy rainfall. Otherwise, today`s forecast
calls for light winds with daytime temperatures around 10 to 20
degrees below normal.

From late tonight through Wednesday morning, the low is forecast
to move across northern Arizona. As it does so, additional
atmospheric moisture from Hurricane Polo will be entrained into
the low. With increased synoptic-scale forcing associated with the
passing low, greater storm activity and higher rainfall rates are
forecast. High-resolution model guidance highlights the eastern
Mogollon Rim and White Mountains as the area with the highest
flood risk with 24 hour rainfall totals up to 3 inches. We will
also see higher 0-6km Bulk Wind Shear, with values ranging from
40-60 kts. Despite the strong shear, forecast CAPE values at or
below 600 J/kg may limit the overall severe thunderstorm threat,
though isolated severe storms cannot be ruled out given the
benefit of forcing from the low. So, all things considered, we
are looking at a moderate/high risk of flooding/flash flooding,
with a lower risk of strong storms producing large hail and severe
wind gusts. A Flood Watch remains in effect for northern Arizona
through midnight Tuesday.

On Wednesday, the low center moves into New Mexico, with chances
for showers and storms primarily remaining across eastern
Arizona. High pressure is forecast to bring a return of dry
weather, with daytime temperatures warming to near average on
Thursday and Friday.

&&

.AVIATION...Monday 28/18Z through Tuesday 29/18Z...MVFR
conditions will be common within bands of steady stratiform rain
and showers moving across the region. Isolated thunderstorms
likely become embedded this afternoon and continue at times into
Tuesday. Expect brief IFR conditions in heavier showers and
thunderstorms, or patchy fog. KPRC-KSEZ-KFLG and surrounding
areas will be on the edge of activity this afternoon and again
overnight, seeing at least brief breaks in rainfall. Winds south
5-15 kts daytime, light and variable overnight. Gusty and erratic
winds near storms.

OUTLOOK...Tuesday 29/18Z through Thursday 01/18Z...Expect
scattered to numerous showers and thunderstorms area wide through
Tuesday afternoon with the focus of precipitation then shifting
towards eastern Arizona heading into Wednesday. Look for areas of
MVFR conditions with brief IFR conditions in heavier showers and
thunderstorms. Daytime winds variable at 5-15 kts Tuesday
afternoon, west to northwest at 5-15 kts Wednesday. Light and
variable at night.est to northwest at 5-15 kts Wednesday. Light and
variable at night.

&&

.FIRE WEATHER...Tonight through Wednesday...Precipitation chances
will peak now through Tuesday with widespread wetting rain and
isolated embedded thunderstorms across the region, becoming more
focused over eastern Arizona by Tuesday evening. This will present a
moderate flood and burn scar flash flood risk. Some precipitation
chances linger in far eastern Arizona Wednesday, drying out
elsewhere. Winds N-NE 10-20 mph on Tuesday, NW-N 5-15 mph on
Wednesday.

Thursday through Saturday...Dry with no precipitation across the
state, minimum RH drops to the 20s and 30s percent by Saturday.
Winds light and variable 5-10 mph Thursday, light and variable most
areas Friday/Saturday with the exception of some winds E 5-15 mph
along the Rim.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Tuesday evening for AZZ004>018-037>040.

&&

$$

PUBLIC...RR
AVIATION...Zanker
FIRE WEATHER...Zanker

For Northern Arizona weather information visit
weather.gov/flagstaff