368
FXUS65 KFGZ 091611
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
911 AM MST Thu Oct 9 2025

.SYNOPSIS...Moisture from the remnants of Tropical Storm
Priscilla will lead to widespread showers and thunderstorms across
northern Arizona through Saturday. Flash flooding will be
possible as a result of the heavy rainfall. Unsettled conditions
continue into the first part of next week, with scattered shower
and thunderstorm activity continuing.

&&

.DISCUSSION...Today...Sub-tropical moisture from the remnants of
Tropical Storm Priscilla has begun to increase across northern
Arizona, with dewpoints just south of the Mogollon Rim already
rising into to lower 50s F. Moisture will continue to increase
through the early morning hours, with a complex of showers and
embedded thunder moving northward through the morning. More
widespread activity looks to move into the region by the late
afternoon hours, especially across the western-half of the state.

Friday and Saturday...The main period of heavy rain moves into the
region by Friday, as large-scale ascent from an approaching trough
moves into the region. These added dynamics combined with the
abundant moisture (PWATs look to be near-record for this time of
year) will result in very efficient rainfall rates during this
period. Thus, the threat of flooding remains very likely, primarily
within a narrow band of heavier precipitation that is expected to
develop. Current hi-res guidance currently favors an area from
Prescott to Williams/Flagstaff to Kayenta to see the heaviest
rainfall. During the day Saturday, the band of heavier precipitation
should begin to shift eastward through the day. Bringing some relief
to the western portion of the state, and then shifting the threat
towards the east. With the band no longer stationary, rainfall rates
don`t look to be as significant, but would be enhanced within areas
of upslope (Mogollon Rim, White Mountains, Black Mesa, and the
Chuska Mountains).

Within the heavier band of precipitation, rainfall amounts of 2-3
inches look probable, which could potentially be higher in the
usual upslope areas. For this reason, a moderate risk for flooding
has been added on Friday. Elsewhere, around 0.50 to 1.5 inches of
rain can be expected.

All and all, there is a significant risk for flooding across the
area with this event. Flash flooding will be a threat, especially
over rain sensitive areas (i.e. burn scars and slot canyons).
However, given the longer duration of the rain event, flooding of
larger waterways (washes, creeks, and rivers) will be a real
possibility.

Sunday through Wednesday...As the trough moves into Arizona, drier
air begins to set in and the threat for heavy rainfall is pushed
into southeastern Arizona. However, unsettled conditions will likely
remain into next week as the moisture is not totally removed.

&&

.AVIATION...Thursday 09/18Z through Friday 10/18Z...Isold -SHRA/-TSRA
through around 18Z, then increasing coverage through the afternoon
and overnight. The highest coverage of precipitation will be west
of a KPAN-KINW-KRQE line. Mainly VFR outside of rain, with MVFR
and local IFR in showers. More persistent IFR conditions may
develop after 06Z over higher elevation areas including KFLG due
to a combination of low clouds, fog, and rain. Look for sustained
winds out of the SE through SW generally less than 10 kts and
gusts between 15 and 20 kts through the period. Gusty conditions
will be possible with any shower/storm.

OUTLOOK...Friday 10/18Z through Sunday 12/18Z...Widespread SHRA/TSRA
expected through the outlook period. Expect widespread MVFR conditions
and areas of IFR due to continuous periods of SHRA/RA and
isolated TSRA. Periods of IFR/LIFR conditions in FG are also
expected over higher elevation upslope areas, including KFLG/KGCN.
Winds on Friday will generally be light, becoming S-SW at 10-20
kts with gusts near 25 kts on Saturday. Gusty/erratic winds will
also be possible in heavier showers/storms.

&&

.FIRE WEATHER...Today and Friday...Widespread wetting rains, with
the highest accumulations expected in Yavapai and Coconino counties.
A Flood Watch will be in effect for most of northern Arizona through
the period. Isolated strong thunderstorms also possible. Winds south
through southeast 5-15 mph each day, but gusty and erratic winds can
be expected near showers/thunderstorms.

Saturday through Monday...The Flood Watch continues Saturday, with
more widespread showers and thunderstorms. Storm coverage becomes
isolated to scattered on Sunday and Monday. Daytime winds southwest
10-15 mph with gusts near 20 mph. Gusty and erratic winds can be
expected near showers/thunderstorms.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Saturday evening for AZZ004>010-012-013-015-
016-018-037>040.

&&

$$

PUBLIC...Humphreys
AVIATION...RR
FIRE WEATHER...JJ

For Northern Arizona weather information visit
weather.gov/flagstaff