912
FXUS65 KFGZ 192013
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
113 PM MST Fri Jul 19 2024

.SYNOPSIS...Scattered showers and thunderstorms are expected each
day through the next week. Temperatures will remain above average
through the weekend with typical afternoon winds.

&&

.DISCUSSION...A moderate monsoonal pattern will continue under the
influence of high pressure aloft over the region through the next
several days.

The upper level high pressure circulation is centered over central
Arizona today and gradually nudging westward. Convective
initiation has begun with isolated to scattered coverage over the
higher terrain areas. Storm strength is somewhat lacking so far,
likely due to less available instability today with the high
parked overhead. As has been the pattern the last several days,
expect scattered storms to continue through this evening while
gradually drifting into the lower elevations. Brief heavy rain and
gusty outflow winds are the main concerns today. Very marginal
instability should limit the threat of larger hail.

We expect a continuation of this general pattern through the
upcoming week. The high pressure circulation will shift west of
Arizona while strengthening over the Great Basin. This will keep
us in a northerly steering flow. Expect daily chances for
thunderstorms, with a focus for late afternoon/evening storms
south of the Mogollon Rim. A slight uptick in moisture looks
likely over the weekend, especially along and south of the rim
which will lead to a slight increase in precipitation chances.
This pattern typically results in some severe storms and heavy
rainfall south of the rim, and Sunday/Monday look like the best
days for this with more storm organization and longevity.
Yavapai/Gila county will see storm chances continue well into the
evening hours throughout this northerly flow regime.

No notable changes in the pattern are expected until perhaps
beyond day 7 when a flattening of the ridge could bring some
drier air into the region, but confidence is low right now.

The presence of the warm ridge and above average heights through
most of the period will continue to bring warmer than average
temperatures. The most susceptible areas are the lower Grand
Canyon and valleys of Yavapai county, including Verde Valley, but
these areas look to remain below any heat warning thresholds.
Regardless, caution should be used in the lower elevations as
temperatures continue to run well above normal for late July.

&&

.AVIATION...Friday 19/18Z through Saturday 20/18Z...Isolated
TSRA/SHRA will begin developing across the region between 18Z and
21Z. Outflow interactions will help generate additional
convection activity while also resulting in gusty erratic winds,
especially when nearby aviation sites. Activity will diminish
after 01-03Z this evening.

OUTLOOK...Saturday 20/18Z through Monday 22/18Z...Daily chances
persist for scattered TSRA/SHRA each afternoon/evening. Periods
of MVFR conditions and gusty, erratic winds near TSRA. Otherwise,
VFR conditions with variable daytime winds 5-15 kts.

&&

.FIRE WEATHER...Today through Sunday...A warm, monsoonal pattern
will continue with daily chances for showers and thunderstorms.
Storms may produce heavy rain and gusty outflow winds. The threat
for heavy rain increases Sunday south of the Mogollon Rim. Outside
of storm activity, expect west to north winds 5 to 15 mph.

Monday through Wednesday...Daily chances for showers and
thunderstorms continue. Gusty and erratic outflow winds, hail,
and heavy rainfall will be the main hazards. An increased threat
for heavy rainfall continues Monday south of the Mogollon Rim.
Winds outside of storms mainly less than 15 mph and variable in
direction.

&&

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

&&

$$

PUBLIC...MCT
AVIATION...RKR
FIRE WEATHER...MCT

For Northern Arizona weather information visit
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