338
FXUS65 KFGZ 190944
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
244 AM 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...Some light showers continue early this morning,
mainly over northern Apache and Navajo counties, with clear to
partly cloudy skies and light winds elsewhere. The center of the
high pressure system is parked right over central Arizona, and the
clockwise circulation around this center can be seen in current
radar loops (showers in NE Arizona moving south, while showers in
Coconino County are moving north). Latest model data continues to
indicate that the center of the high will slowly move westward
over the next few days, and this will bring northerly steering
flow to most of our forecast area starting today, but getting a
bit stronger later Saturday and Sunday. Precipitable water values
are slightly above normal for mid-July south of the Mogollon Rim
and this isn`t expected to change much over the next several days.
Along and north of the Mogollon Rim, moisture values are closer to
normal. 500mb heights will remain high today (596 dam) with
another hot day around the region, but just a bit short of any
warning criteria for our lower elevations. These heights slowly
come down over the weekend and into next week as the high shifts
westward, allowing for a gradual lowering of high temperatures -
though still a few degrees warmer than normal. Scattered showers
and thunderstorms are forecast to develop each day, first over the
higher terrain including the Mogollon Rim/White Mtns by late
morning or early afternoon, and then move southwestward with the
mean steering flow. This pattern is favorable for some strong to
locally severe thunderstorms rolling off the rim into Gila/Yavapai
counties by late afternoon and evening. The main threats with
these storms include strong gusty winds and localized flooding,
though some isolated large hail is also a possibility. This
pattern sticks around for much of next week, though right now
Sunday afternoon and evening are looking particularly favorable
due to higher instability (CAPE) values, and also enhanced
northeasterly steering flow of around 20-25 kts. North of the
Mogollon Rim, coverage of storms should be somewhat lower, but
still in the 30-50% range. Outside of gusty winds with storms,
generally west to northwest winds 5-15 mph are expected into next
week.


&&

.AVIATION...Friday 19/06Z through Saturday 20/06Z...Expect VFR
conditions overnight with SCT-BKN cloud cover above 10,000 feet
AGL, becoming clear by 15Z. Anticipate another round of -TSRA/-SHRA
from 19Z-03Z with the greatest chances along and south of a KGCN-
KFLG-KSOW line. Brief periods of MVFR VIS with mountain
obscuration due to lower cloud cover are likely in heavy storms.
Outside of erratic/gusty outflow winds of up to 35 kts, expect
light winds overnight, becoming northwest 10-20 kts by 20Z.

OUTLOOK...Saturday 20/06Z through Monday 22/06Z...Scattered
showers and thunderstorms with brief periods of MVFR conditions
are anticipated each day from roughly 19Z-03Z. The greatest
chances for direct impacts from storms will be along and south of
a KGCN-KFLG-KSOW line. Besides for gusty/erratic outflows from
storms, expect north-northwest surface winds, 10-20 kts each
afternoon.

&&

.FIRE WEATHER...Today and Saturday...Daily chances for showers and
thunderstorms each afternoon and evening, with the most numerous
storms expected over the higher terrain. Gusty and erratic outflow
winds, small hail, and  heavy rainfall remain the main hazards.
Daytime winds southwest to northwest 5 to 15 mph outside of storms,
along with near-normal to slightly above normal temperatures.

Sunday through Tuesday...Daily chances for showers and thunderstorms
continue each afternoon and evening. Gusty and erratic outflow
winds, small hail, and heavy rainfall will be the main hazards.
Variable winds 5 to 15 mph outside of storms, along with near-normal
to slightly above normal temperatures.

&&

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

&&

$$

PUBLIC...JJ
AVIATION...LaGuardia
FIRE WEATHER...Humphreys

For Northern Arizona weather information visit
weather.gov/flagstaff