871
FXUS65 KFGZ 142254
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
354 PM MST Sat Sep 14 2024

.SYNOPSIS...A few showers will be possible in eastern Arizona
through early Sunday morning with mainly dry weather elsewhere.
Cooler weather with chances for showers and thunderstorms will
move in for later on Sunday and continuing through Monday. Look
for breezy weather on Sunday with windy conditions on Monday. Dry
but cool weather then returns on Tuesday and for the much of next
week.

&&

.DISCUSSION...It`s a pleasant Saturday afternoon around northern
Arizona with seasonable temperatures and light southwest breezes.
Scattered cumulus clouds are developing in the high country as
low level moisture values have increased slightly since yesterday.
Several of the CAMs continue to show some very isolated showers
later this afternoon/evening from around the White Mtns up to I-40
near Holbrook, with dry weather elsewhere. Later tonight, a large
trough begins to push southward through the Pac NW, with some
increasing southerly flow in Arizona. This should help pull some
deeper moisture northward over the next 24 to 48 hours, with a
chance of showers and thunderstorms from Sunday through Monday
evening. The forecast models have generally decreased precipitation
amounts in our area, as well as pushing the higher amounts farther
east. This is reflected in our latest forecasts, but there is
some disagreement to note as several hi-res models/U of A WRF
runs indicate more activity farther west including
Prescott/Flagstaff. Felt the NBM PoPs were too low in these areas
especially later Sunday into Monday and so these were adjusted up
quite a bit. Otherwise, the other threats we have been mentioning
also seem to have decreased some over the last 24 hrs, including
the flash flood and severe weather threats. The latest
probabilities for CAPE >500 J/kg coinciding with deep-layer wind
shear >30kts (which would indicate a better chance of
strong/severe storms) are down below 20% Sunday night/Monday,
these values were 30-50% from Yavapai County to Gila County on
yesterdays model runs. The other issue on Monday looks to be wind
speeds as the upper low dives into Nevada. Southwest winds are now
forecast to reach 15-30 mph sustained with gusts 35-45 mph, so a
Wind Advisory may need to be issued for Monday afternoon.

Tuesday through Friday - cooler, breezy, and mainly dry weather is
expected. Another upper low is forecast to dip down from the Pac
NW through Utah by Thursday. Daytime temperatures will be 5-10
degrees below seasonal averages, with some near-freezing lows for
the more favorable spots in the high country. There may be enough
moisture available for a few showers from around Flagstaff north
and west on Thursday, but this low won`t have much of a moisture
tap to work with.

&&

.AVIATION...Sunday 15/00Z through Monday 16/00Z...Mainly VFR
conditions persist through the period with FEW-SCT cloud cover
near 5,000 feet AGL. Southerly winds around 10-15 kts will ease
early this evening, becoming variable around 5 kts. Cloud cover
increases towards the east for Sunday with chances for isolated to
scattered -SHRA/-TSRA mainly along and east of a KPAN-KFLG-Four
Corners line by 20Z. Outside of gusty outflows from any storms,
plan on southwest winds, 15-25 kts.

OUTLOOK...Monday 16/00Z through Wednesday 18/00Z...Isolated to
scattered showers and thunderstorms persist Sunday night through
Monday with greatest chances across eastern Arizona. Plan on SCT-
BKN cloud cover below 10,000 feet AGL during this time with light
southerly breezes, ~10 kts, overnight followed by a return of
gusty southwest winds, 25-35 kts, after 17Z Monday. Widespread VFR
conditions are expected Monday night and Tuesday with mostly clear
skies. Southwest winds will remain elevated on Tuesday, 20-30 kts.

&&

.FIRE WEATHER...This Evening through Monday...Increasing moisture
from the south will lead to a slight chance of showers and
thunderstorms late today in eastern Arizona. Moisture will continue
spreading northward late tonight through Monday for better chances
of precipitation for much of northern Arizona. Afternoon southwest
winds 10 to 20 mph Sunday, increasing to 15-30 mph with gusts 35-45
mph on Monday.

Tuesday through Thursday...Cooler, breezy, and mainly dry. Another
low pressure system could bring a few showers to northwest Arizona
Thursday. Southwest winds 15-25 mph each day.

&&

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

&&

$$

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

For Northern Arizona weather information visit
weather.gov/flagstaff