Flash Flood Warning 327, NWS Flagstaff, AZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
149 PM MST Wed Sep 14 2022

.SYNOPSIS...Scattered showers and thunderstorms will gradually
diminish over northern Arizona later this evening. Drier and more
seasonable weather is forecast Thursday through the end of the
week. Breezy conditions will develop Saturday and Sunday
afternoons. Chances for precipitation will return to the forecast
Monday through Wednesday.

&&

.DISCUSSION...Scattered thunderstorms will continue to develop
primarily across areas north of I-40 this afternoon. The
convection has been moving at a pretty good clip so far.
Therefore, continue to think the flash flood threat is low through
the remainder of the day. Convection should wane after sunset
with the loss of daytime heating.

Shortwave ridging and dry southwesterly flow aloft should allow
for dry conditions to develop across northern Arizona Thursday
through the weekend. Medium range guidance continues to prog a
potent upper low digging in just off the California coast over the
weekend. This will result in breezy conditions developing across
northern Arizona, primarily Saturday and Sunday afternoons. This
should also result in a gradual warming trend through the weekend.

By Monday, monsoonal moisture should begin its push back into the
region. For now think most convection should be confined to the
White Mountains Monday afternoon. However, this could change as we
get closer to the event. Better chances for thunderstorms are
forecast Tuesday given the expected position of the upper low over
the Great Basin and upper high over the Southern Plains.

There's quite a bit of uncertainty regarding when the moisture
will be swept out of the region next Wednesday and beyond. This
all hinges on when the upper low decides to lift into the mean
flow aloft and takes all the moisture with it.

&&

.AVIATION...For the 00z TAF package...Scattered showers and
thunderstorms mainly north of I-40 will diminish between 00z-02z
Thursday. Surface winds will generally remain light at 5-15 knots,
except in the vicinity of thunderstorms. Patchy fog will possible
after midnight tonight. Dry conditions are forecast for Thursday.
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Scattered showers and thunderstorms across
northern Arizona will diminish later this afternoon and evening.
Dry conditions and relatively warmer temperatures are forecast for
Thursday and Friday.

Saturday through Monday...Dry conditions and a warming trend will
continue through the weekend. Breezy southwesterly winds are
forecast each afternoon Saturday through Monday. There will be a
slight chance for thunderstorms in the White Mountains Monday
afternoon.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

&&

PUBLIC...TM
AVIATION...TM
FIRE WEATHER...TM

For Northern Arizona weather information visit
weather.gov/flagstaff