177
FXUS65 KFGZ 121810
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1110 AM MST Tue Aug 12 2025

.SYNOPSIS...One last day of hot and mainly dry conditions today,
before increasing monsoonal moisture and cooler temperatures set
in through the end of the week. The best chances for thunderstorms
will be Thursday and Friday. Drier and warmer conditions look to
gradually return by the start of next week.

&&

.DISCUSSION...Today...Another round of isolated showers and
thunderstorms looks to develop this afternoon, mainly along and
south of the Mogollon Rim. Elsewhere, hot and dry conditions look
to remain across the area. While a few brief heavy downpours and
small hail will be possible with any stronger storm, gusty winds
look to be the primary threat this afternoon with these storms.

Wednesday through Friday...The high looks to gradually shift
eastward across the southwest as a trough sets up over the
northwestern US. This looks to open the door for more favorable
northward advection of monsoonal moisture, and thus better chances
for at least scattered showers and thunderstorms each day.

The coverage any given day however remains somewhat uncertain, as it
will be highly dependent upon just how far northward the moisture
can get as well as any remaining debris cloud from the previous
day. Model soundings also still show an strong inverted-v profile,
especially in the first couple of days, indicative of a still dry
sub- cloud layer despite the increased PWATs. Thus, gusty winds
still look to be the primary threat, more so than flash flooding.
Some localized instances of flooding can not be totally ruled out
from any heavier storms and/or in rain sensitive areas.

Outside of the precipitation chances, a return of cooler, more
seasonable temperatures is expected for the second-half of the
work week.

Saturday through Monday...By the weekend, the aforementioned
trough looks to move closer to Arizona. This looks to bring a
return of drier air to the area, and gradually reduce chances for
precipitation each day. Temperatures also look to gradually rise
by the start of next week, along with breezier winds.

&&

.AVIATION...Tuesday 12/18Z through Wednesday 13/18Z...VFR
conditions. ISO -SHRA/-TSRA between 19Z-03Z, mainly south and east
of a KPRC-KFLG-KRQE line. Winds are W-NW 5-10 kts with gusts
15-20 kts, then light and VRB overnight. Gusty and erratic winds
are possible near storms.

OUTLOOK...Wednesday 13/18Z through Friday 15/18Z... Primarily VFR
conditions. ISO-SCT SHRA/TSRA each afternoon, especially over the
higher terrain. Brief drops to MVFR conditions with gusty/erratic
winds can be expected in and around storms. Daytime winds are W
5-15 kts with gusts 15-25 kts. Winds are light and VRB during the
overnight periods.

&&

.FIRE WEATHER...Today and Wednesday...Hot and mainly dry conditions
continue today, outside of a slight chance for thunderstorms from
the Mogollon Rim and southward. Better chances for thunderstorms and
cooler temperatures then begin to set in on Wednesday, mainly from
the Grand Canyon along Mogollon Rim and south. Daytime winds
west/northwest at 5-15 mph. Gusty outflow winds possible in and
around thunderstorms.

Thursday through Saturday...Turning cooler. Scattered showers and
thunderstorms possible each afternoon, especially Thursday and
Friday. Best chances for precipitation will be over the higher
terrain. Winds west/southwest around 10-20 mph each day. Gusty
outflow winds possible in and around thunderstorms.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 8 PM MST Thursday for AZZ006.

&&

$$

PUBLIC...Humphreys
AVIATION...Humphreys
FIRE WEATHER...Lewandowski

For Northern Arizona weather information visit
weather.gov/flagstaff