435
FXUS65 KFGZ 152203
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
303 PM MST Wed May 15 2024

.SYNOPSIS...Scattered showers and thunderstorms will continue
throughout the day with isolated showers and storms continuing
overnight. Rain and thunderstorm chances remain Thursday for
portions of northern and northeast Arizona. A brief ridge Friday
through the weekend over the region will result in warmer and
drier conditions. Unsettled weather returns next week.

&&

.DISCUSSION...The closed low along with a longwave trough to the
northeast are working in conjunction to bring showers and
thunderstorms to a good portion of northern Arizona. Mostly light
westerly winds are being impacted significantly by the erratic
gusts from the scattered storms. A few of the stronger storms
have produced wind gusts of 40 to 50 mph as outflow boundaries
propagate in various directions. Be aware, thunderstorms do not
have to be directly overhead to bring hazardous winds and/or
lightning. These gust fronts continue to trigger additional
activity, tapping into the 250-500 J/kg of CAPE across the area.
Most of the gauges where precipitation has fallen thus far have
recorded only a few hundredths of an inch. However, heavier
showers are impacting localized areas along the Mogollon Rim,
Coconino Plateau, and Black Mesa with radar indicated QPE of 0.5"
to 1.25". Additional isolated strong storms and rainfall will be
continue to be possible, especially over high terrain.

Tonight through Thursday...The scattered showers and storms will
continue through the afternoon and evening hours before shifting
eastward as the low to our south tracks eastward. More isolated to
widely scattered showers and convection will linger overnight,
primarily be relegated to Navajo County and Apache County. While
the dynamics will not be nearly as conducive for precipitation
Thursday, the ECMWF and GFS show a small shortwave ripple through
eastern Arizona. This wrinkle in the atmosphere along with left
over moisture will allow for a slight chance of rain. The best
chances will be along the Arizona/New Mexico border and White
Mountains (20-35%) that will extend along the Mogollon Rim as far
west as the Flagstaff area (10-15%). Much of western Arizona is
expected to remain dry tomorrow with diminishing cloud cover. Once
again, widespread heavy rainfall is not forecast with precipitation
amounts of less than 0.1" likely.

Friday through Sunday...By Friday, an upper-level ridge will begin
to form across the Southwest U.S., leading to a warming and drying
trend that will extend through the weekend. Afternoon highs will
be roughly 5 degrees above average each day. Winds do strengthen
out of the southwest, becoming breezy each afternoon as a longwave
trough to our north pushes against the ridge, tightening pressure
gradients. Overall, winds are forecast to remain below advisory
levels with gusts of 25 to 35 mph expected.

Monday through Wednesday...More unsettled conditions are expected
as models show a trough pushing into the region to start next
week. There is low confidence that this system will have the
moisture required to bring precipitation to Arizona. Anticipate
another increase in the already breezy west-southwest winds along
with temperatures cooling to near to just below seasonal norms.
These winds along with drier conditions will push us towards near
critical fire weather conditions once again. However, the rainfall
we are currently experiencing should help somewhat in this regard.
More updates to follow.

&&

.AVIATION...Wednesday 15/18Z through Thursday 16/18Z....Mainly VFR
expected. Brief periods of MVFR or lower conditions in SHRA/TSRA.
Southwest to west 10-20 kts becoming light and variable after
02Z. Gusty, outflow winds around 30-40 kts possible.

OUTLOOK...Thursday 16/18Z through Saturday 18/18Z...Mainly VFR
conditions expected. Mainly west winds 10-20 kts each afternoon.

&&

.FIRE WEATHER...Tonight through Friday...Scattered showers and
thunderstorms will continue through tonight, becoming more isolated
on Thursday. Southwest to west winds at 5-15 mph through this
evening, becoming west to northwest on Thursday. Erratic outflow
winds up to 40 mph possible due to storms. Dry conditions return on
Friday. South to west winds 10-20 mph with afternoon RH values
between 10-20%.

Saturday through Monday...Warmer and drier weather conditions are
expected through the weekend. Southwest to west winds 15-25 mph
gusting 30-35 mph, increasing to 35-40 mph on Monday. Afternoon
RH values will range between 5-15%, increasing to 10-20% on Monday.

&&

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

&&

$$

PUBLIC...Mazon
AVIATION...Meola
FIRE WEATHER...Meola

For Northern Arizona weather information visit
weather.gov/flagstaff