168
FXUS65 KFGZ 101746
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1046 AM MST Fri May 10 2024

.SYNOPSIS...Mild temperatures will continue through Saturday with
isolated to scattered afternoon showers and thunderstorms along
and north of I-40. Warmer temperatures arrive starting Sunday,
with another chance for a few showers or storms Tuesday and
Wednesday. Expect typical spring breezes through the period.

&&

.UPDATE...With a weak, upper-level low pressure system over the
Great Basin and into the Southwest currently, expect east-
southeast winds this morning to transition to south-southwest,
10-20 mph, by 12-2 pm MST. Smoke impacts from prescribed burns
near Flagstaff and the White Mountains today look to be similar to
yesterday`s as wind patterns will be the same. This all depends on
overall smoke production from the ongoing burns.

Otherwise, anticipate mild temperatures and dry conditions with
much of northern Arizona forecast to see minimum humidity values
of 10-15% this afternoon. Locations along the Utah border,
including the Kaibab Plateau, could see a few light rain showers/
stray thunderstorm for this afternoon, due to a bit more moisture
and instability. Areas along and north of I-40 could also see
virga showers develop this afternoon, similar to what was
experienced yesterday. Not much, if any, rainfall is expected for
these locations due to the very dry air at the surface, however,
it could make for some nice sunset pictures later this evening.

The forecast remains on track with no changes needed at this time.

&&

.PREV DISCUSSION /419 AM MST/...Low pressure is located across the
southwest US this morning, centered over southern Utah and Nevada.
Cooler temperatures in the mid levels associated with this trough
have allowed for some cloud buildups during the afternoon even
though low level moisture is meager (dewpoints teens/20s). Virga
and a few sprinkles developed from around Flagstaff northward late
Thursday afternoon. As the low moves a bit farther toward the
southwest this afternoon, the better chances for a shower or
thunderstorm (20-30%) will be from around the Grand Canyon
northward. Otherwise, look for a nice day around the region with
relatively light winds and highs near normal. For Saturday - the
low is forecast to move back eastward and cross northern Arizona.
Instability and mid level moisture increase, and we have
introduced a 20-40% chance of showers and thunderstorms from the
the Flagstaff region north and east, with the higher values near
the four corners. This activity will be high-based as surface
dewpoints will still be only in the 20s, meaning any shower could
produce gusty/erratic winds but not much rain.

Sunday and Monday - the low shifts well east of the state as brief
ridging develops over the region. There will still be some cloud
buildups over the mountains each afternoon, but mid level
temperatures will warm a few degrees keeping instability down and
decreasing the chance of showers to under 10%. Afternoon
temperatures will warm to around 5 degrees above normal by Monday.

Tuesday and Wednesday - a weak low off the Pacific is forecast to
move eastward into the state. More mid level moisture and mid-
level cooling will lead to some isolated afternoon showers mainly
over high terrain. Again these should be high-based with little
in the way of rainfall but still producing some gusty winds.
Beyond Wednesday, model spread increases but the overall trend
looks like high pressure building over the western US.

&&

.AVIATION...Friday 10/18Z through Saturday 11/18Z...VFR conditions
should mostly prevail through the TAF period. Isolated -SHRA/-TSRA
will be possible near/north of KGCN after 18Z. Brief periods of
smoke may reduce visibility at/near KFLG midday today, and again
overnight at KFLG, KSEZ, and KINW due to prescribed burns. Expect
winds to gradually shift to mostly SW this afternoon at 10-20 kts.

OUTLOOK...Saturday 11/18Z through Monday 13/18Z...VFR conditions
should prevail outside of slight chances for -SHRA/-TSRA Saturday
afternoon. Precipitation will likely stay along and north of a
KSEZ-KRQE line. Periods of FU/HZ possible near prescribe burns,
mainly the KFLG and KSEZ terminals. Look for W winds 10-25 kts on
Saturday afternoon, becoming W-NW winds on Sunday. Light winds
return during the overnight timeframe.

&&

.FIRE WEATHER...Today and Saturday...Look for below normal
temperatures each afternoon, with isolated showers/storms mostly
along and north of I-40. Winds overnight should generally be light,
but localized breezes are possible. Expect south-southwest winds 10-
20 mph by this afternoon, becoming west winds 10-25 mph on Saturday.

Sunday through Tuesday...Temperatures will warm to a few degrees
above normal through the beginning of the week. Afternoon
precipitation chances are low each afternoon, but not zero. Look for
west-northwest winds 10-20 mph on Sunday, becoming west winds around
5-15 mph Monday and Tuesday.

&&

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

&&

$$

PUBLIC...LaGuardia/JJ
AVIATION...MCT
FIRE WEATHER...MCT

For Northern Arizona weather information visit
weather.gov/flagstaff