025
FXUS65 KFGZ 300434
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
934 PM MST Tue Jul 29 2025

.SYNOPSIS...Daily chances for showers and thunderstorms continue,
initially across the White Mountains before spreading north and west
by the end of the week. Drier and warmer weather looks to return
over the weekend and into next week. In any event, remember the fire
danger remains high as June-like weather continues.

&&

.DISCUSSION...Over the coming days high pressure will gradually
build over Arizona. However, the high will continue to battle a
persistent trough along the west coast of the United States.
While additional moisture will move across northern Arizona a
warm air cap, shear in the mid-levels and limited instability is
expected to inhibit widespread thunderstorm activity. The best
chances for area wide showers and thunderstorms will be Thursday
and Friday with 20-40% coverage. It will remain breezy each
afternoon with a fire danger more like June than July. Monsoon
where are you?

The rest of today...Dry air will remain in place for much of
northern Arizona. The high has built further westward over the past
24 hours with a slight moisture increase from near a Payson-Winslow-
Window Rock line southward. As a result, look for isolated afternoon
and evening showers and thunderstorms across this area with storm
motion generally from north to south. Northwest of the line above,
mainly dry and hot conditions will continue. An Extreme Heat Warning
remains in effect for the lower elevations of the Grand Canyon
through Sunday where high temperatures will remain in excess of
110 degrees.

For Wednesday through Friday...High pressure will continue to nudge
westward. Most locations will only see a slight uptick in moisture
and thunderstorm activity (around 10-20% coverage) on Wednesday with
the best chances over the eastern Mogollon Rim and White
Mountains with 40-50% coverage of showers/storms. As the high
builds further west the Gulf of California will open up with a
push of deeper moisture across the area on Thursday and Friday.
While an increase in shower and thunderstorm coverage is
anticipated storms will struggle to become strong due to the
combined influence of limited instability, a capping layer aloft
and mid-level wind shear a bit strong for the weak instability. At
this time we are looking at only a 20-40% coverage of storms
across northern Arizona on Thursday and Friday with any heavy
downpours remaining isolated. The influence of the trough and
passing disturbances to the northwest will insure breezy afternoon
winds each day and an elevated fire danger, especially across
northwest Arizona.

Through the weekend into early next week...The center of a strong
high pressure system becomes established over southern Arizona. The
result for northern Arizona will be that a drier air mass will push
in from the west. Low grade monsoon activity may continue,
primarily over the White Mountains are, but mainly dry and breezy
conditions will prevail elsewhere.

&&

.AVIATION...Wednesday 30/06Z through Thursday 31/06Z...Mainly VFR
conditions. MVFR conditions possible near and north of a KGCN-KPGA
line in HZ/FU. ISO -SHRA/-TSRA with gusty outflow winds possible in
vicinity of KSOW/KJTC from 20Z to 02Z. Daytime winds W/SW 5-15 kts
with gusts 20-25 kts.

OUTLOOK...Thursday 31/06Z through Saturday 02/006Z...Mainly VFR
conditions. MVFR conditions possible near and north of a KGCN-KPGA
line in HZ/FU. ISO -SHRA/-TSRA with gusty outflow winds possible
each afternoon over the higher terrain, mainly from KPAN-KFLG-KRQE
and southeast. Daytime winds SW 10-20 on Thursday, subsiding to 5-15
kts on Friday.

&&

.FIRE WEATHER...This afternoon through Thursday...Hot temperatures,
low humidity, and breezy afternoon southwest winds expected. Slight
chances for showers/storms today and Wednesday mainly east of a
Payson to four corners line. Storm chances increase slightly
Thursday and spread north and west, though much of the activity will
be high-based producing gusty/erratic winds and a few dry lightning
strikes. Otherwise, afternoon southwest winds 10-20 mph gusting near
25 mph. Minimum RH values between 5-15% for much of northern
Arizona, with values closer to 15-30% towards the White Mountains.

Friday through Sunday...Hot and mostly dry with breezy southwest
winds. Chances for showers/storms Friday, then much drier conditions
for the weekend. Outside of the White Mountains, most showers and
thunderstorms will produce only light rainfall. Minimum RH 15-30%
Friday, dropping to 7-20% on Saturday and Sunday. Outside of
gusty/erratic winds near storms, look for southwest winds 10-20 mph.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 7 PM MST Sunday for AZZ006.

&&

$$

PUBLIC...McCollum
AVIATION...Humphreys
FIRE WEATHER...JJ

For Northern Arizona weather information visit
weather.gov/flagstaff