244
FXUS65 KFGZ 121133
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
433 AM MST Fri Jul 12 2024

.SYNOPSIS...Hot temperatures will continue today, with a slight
cooling trend over the weekend. Increasing moisture each day with
widespread chances for afternoon showers and thunderstorms
continuing into early next week.

&&

.DISCUSSION...Strong high pressure is currently over southern UT
and northern AZ early this morning. This slight shift in position
from where the high was yesterday should allow for better moisture
advection leading to increased chances for showers and
thunderstorms across the region today. The steering flow should
turn a bit more east to northeast today. This will keep the
initial storm development along and south of the Mogollon Rim,
though expect there to be a bit more activity from the Grand
Canyon eastward through Window Rock than there was on Thursday.
Modest instability (500-1000 J/kg CAPE) and some shear (15-30 kts)
will be present today so anticipate that a few storms may be
strong to severe and capable of producing damaging winds, hail,
and brief heavy rainfall this afternoon.

Heat will remain an issue, especially in Grand/Glen Canyons today.
Excessive Heat Warnings remain in effect for areas below 4000 feet
through 8 PM tonight. With the increased cloud cover expected across
central Arizona, temperatures should be slightly cooler and fall
below warning criteria across Yavapai county.

By Saturday, the high sets up near Four Corners in a typical monsoon
pattern leading to more widespread storms across the region. With
the increasing moisture, we should see things shift from a severe
threat to more of a flash flood threat through the weekend. PWATs
don`t look anomalous for mid-July but storms will be capable of
producing torrential rainfall which could result in flash flooding.
Something we will will need to keep an eye on as we head through
the weekend. While still hot, cloud cover will be higher due to
the increase in moisture and should keep things slightly cooler
over the weekend.

The monsoon pattern looks to change little as we head into the new
week, keeping good chances for showers and thunderstorms across
northern and central Arizona. The high starts to wobble a bit to the
west early in the week which will likely start to decrease the
coverage of storms as we head into the latter half of next week.

&&

.AVIATION...Friday 12/12Z through Saturday 13/12Z...Mainly VFR
conditions are expected through the period with SCT-BKN cloud
cover near 10,000 ft AGL developing after 17Z. Scattered showers
and thunderstorms are anticipated from 19Z-03Z with greatest
chances along and south of a KGCN-KFLG-KSOW line. Brief periods of
MVFR conditions at KPRC-KSEZ are likely due to TSRA. Outside of
gusty, 20-30 kts, erratic outflow winds from storms, expect
southeast to southwest winds 10-15 kts through 03Z.

OUTLOOK...Saturday 13/12Z through Monday 15/12Z...Widespread
showers and thunderstorms are expected each afternoon and evening
through Monday. Periods of MVFR conditions are possible at any
regional terminal due to TSRA, otherwise anticipate VFR. Besides
for gusty outflows from storms, west-southwest winds 10-20 kts are
forecast each day.

&&

.FIRE WEATHER...Today and Saturday...Hot temperatures will persist
for today, followed by a slight cooling trend beginning on Saturday.
Monsoonal moisture will increase each day with scattered showers and
thunderstorms expected for this afternoon and evening, becoming
widespread for Saturday. Outside of erratic outflow winds from
storms, anticipate a return of southerly winds, 10 to 20 mph, each
afternoon.

Sunday through Tuesday...Widespread showers and thunderstorms are
likely Sunday and Monday with the greatest chances along and south
of the Mogollon Rim and the White Mountains. Coverage becomes more
scattered on Tuesday as moisture decreases slightly. Near average
temperatures are forecast each day along with west-northwest winds,
15 to 20 mph.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...

Excessive Heat Warning until 8 PM MST /9 PM MDT/ this evening
for AZZ005-006.

&&

$$

PUBLIC...Meola
AVIATION...LaGuardia
FIRE WEATHER...LaGuardia

For Northern Arizona weather information visit
weather.gov/flagstaff