818
FXUS65 KFGZ 272308
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
408 PM MST Mon Jul 27 2026

.SYNOPSIS...Monsoon moisture remains in place, but high pressure
remains centered over New Mexico. This is keeping the potential
for showers and thunderstorm mostly contained to the higher
terrain during the afternoon and evening hours today. Chances for
afternoon and evening showers and thunderstorms will continue
Wednesday, mainly for the higher terrain, before temperatures
start rising Thursday and remaining elevated this weekend.

&&

.DISCUSSION...Visible satellite imagery shows a developing
cumulus field over the higher terrain, but the development into
showers and thunderstorms appears to be suppressed by the high
over New Mexico, despite the presence of the monsoonal moisture.
Still expecting isolated to scattered showers and thunderstorms to
develop over the higher terrain later this afternoon, with storm
motion pushing convection toward the north-northeast today.
Convection south of the Mogollon Rim is expected to be limited,
mostly associated with any outflows that push activity southward.

Forecast guidance continues to support the high pressure
weakening slightly Tuesday and Wednesday, before strengthening
again as it moves westward later this week. This may allow a
slight increase in showers and thunderstorms Tueday and Wednesday,
thought the greatest chance remains over and near the higher
terrain. As the high strengthens and shifts westward later this
week, temperatures will begin to climb Thursday and continuing
into the weekend. Based on the consistency of guidance supporting
increasing temperatures, and drier air for later this week and
weekend, an Extreme Heat Warning was issued for the Grand Canyon,
below 4000 feet, starting 10 AM MST Thursday, and then extending
to Yavapai County valleys and basins below 4000 feet and to Marble
and Glen Canyons, and Oak Creek and Sycamore Canyons, including
Sedona, starting 10 AM MST/11 AM MDT Friday. These hazards are
expected to continue trough 8 PM MST/9PM MDT Sunday.

&&

.AVIATION...Tuesday 28/00Z through Wednesday 29/00Z...Mainly VFR
conditions. ISO-SCT SHRA/TSRA through 03Z then SCT SHRA/TSRA
return after 18Z. Brief MVFR/IFR conditions and gusty, erratic
winds in stronger storms. Outside of storms, expect generally
light or terrain driven winds.

OUTLOOK...Wednesday 29/00Z through Friday 31/00Z...Mainly VFR
conditions. ISO-SCT SHRA/TSRA from 18Z-03Z each day, with
greatest coverage across or near higher terrain features. Brief
MVFR/IFR conditions and gusty, erratic winds in stronger storms.
Outside of storms, expect generally light or terrain driven winds.

&&

.FIRE WEATHER...Tuesday and Wednesday...Expect an active Monsoon
pattern to continue through the period, with afternoon/evening
showers and thunderstorms each day. Highest coverage of storms will
be over the higher terrain of central Arizona, with isolated to
scattered activity elsewhere. Gusty and erratic winds, hail, and
flash flooding are continued threats within stronger storms. Away
from storms, winds will be generally southwest to west at 10 mph or
less. Temperatures will be slightly above normal for locations that
do not receive rainfall.

Thursday through Saturday...A downtrend in Monsoon activity is
expected through the period, with isolated storms along the higher
terrain each day. Away from cloud cover and rainfall, temperatures
will rise to possibly the warmest of the year so far. Winds will be
generally light and variable at 5 to 15 mph.

&&

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

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

&&

$$

PUBLIC...Schank
AVIATION...Meola
FIRE WEATHER...Lewandowski

For Northern Arizona weather information visit
weather.gov/flagstaff