757
FXUS65 KFGZ 262317
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
417 PM MST Fri Jul 26 2024

.SYNOPSIS...Look for a good chance of showers and thunderstorms
today, especially along and south of I-40. Over the weekend, a
downward trend in storm activity is expected for much of northern
Arizona, as a drier air mass moves in from the west. Accompanying
the drier air will be locally breezy afternoon southwest winds and
slightly cooler temperatures.

&&

.DISCUSSION...Outflows/thunderstorms now pushing south and/or
southwest of the Mogollon Rim/White Mtns this afternoon, about as
expected. Training could lead to Flash Flooding, especially south of
the Mogollon Rim. Increased shear and the dry layer presence aloft
may also lead to isolated larger hail development, again, most
likely south of the Mogollon Rim.

After a good chance of showers and storms today, look for a near
shutdown of monsoon activity through at least early next week with
any remaining activity being relegated to our east-central zones.

Saturday through Wednesday, the high pushes southward under the
influence of a passing trough to the north. Drier air will push
across the area with a near shutdown of showers and storms except
for the area along and south of a Heber to St. Johns line. The
approach of the trough will strengthen pressure gradients with
afternoon southwest winds at 10 to 20 mph, gusting 25 to 30 mph on
Saturday/Sunday. From Monday into Wednesday, troughing will begin to
weaken and high pressure gradually reemerge with weakening pressure
gradients and associated afternoon winds. Look for slightly cooler
daytime temperatures for much of the period, as the influence of the
high aloft abates.

Thursday and the end of next week, forecast models show the last of
the Pacific Northwest troughs lifting and moving to the east with
the high amplifying back over the western states. If this pattern
emerges the door would once again open to moist low-level flow from
over the Gulf of California and thunderstorm outflow from over
northwest Mexico/southeast Arizona to push moisture back northward
across Arizona. However, any additional trough energy dipping down
from Canada would delay the northward shift of the high.

&&

.AVIATION...Saturday 27/00Z through Sunday 28/00Z...Isolated to
scattered -TSRA/-SHRA persist through 03Z, tapering thereafter.
Mainly VFR conditions can be expected through the period with
MVFR/IFR VIS likely in stronger storms. Calm conditions overnight
with drier conditions likely on Saturday.-SHRA/-TSRA will be
confined to the White Mountains region. Outside of erratic
outflow winds of up to 30 kts near storms, expect westerly winds
10-20 kts for the remainder of the afternoon, becoming southwest
15-25 kts by 18Z Saturday..

OUTLOOK...Sunday 28/00Z through Tuesday 30/00Z...VFR conditions
are expected through the weekend as a drying trend develops.
Isolated showers and thunderstorms will be confined to the White
Mountains each afternoon. Anticipate west-southwest winds 15-20
kts in the afternoon.

&&

.FIRE WEATHER...Saturday and Sunday...A drying trend for this
period. Any showers/ thunderstorms mainly confined to the eastern
Mogollon Rim/southern Apache County. Afternoon southwesterly winds
15 to 25 mph both days.

Monday through Wednesday...The drying trend continues, with minimum
humidity falling to 10 to 25 percent. Precipitation chances limited
to southern Navajo and Apache counties. Afternoon southwesterly
winds decreasing to 10 to 20 mph.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

PUBLIC...Peterson/McCollum
AVIATION...LaGuardia
FIRE WEATHER...Peterson

For Northern Arizona weather information visit
weather.gov/flagstaff