172
FXUS65 KFGZ 292316
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
416 PM MST Wed Jul 29 2026

.SYNOPSIS...Showers and thunderstorms are starting to develop
over the higher terrain due to clear skies and daytime heating. A
complex of thunderstorms is also moving through far northwest
Arizona and into Utah, and outflow from this complex may trigger
more showers and thunderstorms in northwest Arizona this
afternoon. Thursday and through the weekend, shower and
thunderstorm coverage will be isolated and mainly contained to the
higher terrain as daytime high temperatures soar, likely reaching
the warmest readings so far this year.

&&

.DISCUSSION...The weak MCV is continuing to move north-northeastward and showers
and thunderstorms are pushing into Utah. Mostly clear skies are
leading to showers and thunderstorms to develop along the higher
terrain of the Rim, and we should start to see showers and
thunderstorms over the White Mountains over the next couple of
hours as well. Decent southerly flow is expected to push
developing showers and thunderstorms northward, which may limit
the threat for flash flooding from individual storms, but any
back-building storms, caused by outflow from thunderstorms
pushing southward will create localized areas of higher risk for
flash flooding through the afternoon and early evening hours.
Shower and thunderstorm activity should settle down tonight.

For Thursday and into the weekend, the high over New Mexico is
expected to move westward and strengthen, This slowly introduces
drier, mid-level air and subsidence, causing the Monsoon activity
will slow down. We don`t expect a total stop, but it will be slow
through the weekend. The high may return to a more favorable
location by next week, with easterly steering flow returning, but
this outlook could change in a week and will be monitored. The
relocation and strengthening of the high, with the slow down of
the Monsoon, will cause temperatures to soar. This will cause many
locations to reach the warmest temperatures so far this year.
Extreme heat warnings remain in effect for the Grand Canyon,
Yavapai and northern Gila Counties below 4000 ft, as well for
Marble and Glen Canyon, including the city of Page, and Oak Creek
and Sycamore Canyons, including the city of Sedona.

&&

.AVIATION...Thursday 30/00Z through Friday 31/00Z...Mainly VFR
conditions, MVFR possible near heavier showers/storms. Scattered
showers/storms mainly north of I-40 through 03Z. Winds SW 5-15kts
daytime, light and variable or terrain driven overnight. Gusty
erratic winds up to 40kts possible near storms.

OUTLOOK...Friday 31/00Z through Sunday 02/00Z...Mainly VFR
conditions. Isolated showers/storms each afternoon with best
chances near the White Mountains. Winds SW 5-15kts daytime, light
and variable or terrain driven overnight. Gusty erratic winds up
to 40kts possible near storms.

&&

.FIRE WEATHER...Thursday and Friday...A downturn in precipitation
chances begins on Thursday with best chances being over the Rim and
the White Mountains. Temperatures warm to 5-10 degrees above
average. Winds SW 5-15 mph. Minimum RH values 15-30% Thursday, 10-
25% Friday.

Saturday through Monday...Hot with temperatures 10-15 degrees above
average. Only precipitation chances are mainly confined to the White
Mountains this weekend, with a slight uptick in monsoon activity
over the higher terrain starting Monday. Winds will be generally
light and variable at 5 to 15 mph. Minimum RH values 7-20% Saturday,
8-25% Sunday, 10-30% Monday.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning from 10 AM MST /11 AM MDT/ Friday to 8 PM
MST /9 PM MDT/ Sunday for AZZ005-018-037-038.

Extreme Heat Warning from 10 AM Thursday to 8 PM MST Sunday for
AZZ006.

&&

$$

PUBLIC...Schank
AVIATION...Zanker
FIRE WEATHER...Bernhart

For Northern Arizona weather information visit
weather.gov/flagstaff