Flash Flood Warning 191, NWS Flagstaff, AZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
905 AM MST Sat Aug 13 2022

.SYNOPSIS...Daily showers and thunderstorms will continue across
northern and central Arizona through the weekend, maintaining an
enhanced threat for flash flooding. Remember, turn around, don't
drown.

&&

.UPDATE...Unsurprisingly, cloud cover this morning is inhibiting
convective initiation across much of northern Arizona. An
impressive mesoscale vortex is spinning over northern Yavapai
County. While not producing much rainfall, its persistence has led
to a determined batch of unbroken skies. How quickly this cloud
cover dissipates will dictate how quickly instability can build in
the lower atmosphere. This instability is an important ingredient
for strong convective storms. Overall, today's activity looks
delayed compared to yesterday's early start. Storms will likely
form first over the eastern Rim and White Mountains, where skies
are already clear. Any storms that form today have plenty of
moisture to work with, guaranteeing heavy rainmakers in certain
areas.

&&

.PREV DISCUSSION /110 AM MST/...Deep saturation, above average PW
values and surface dewpoints, along with light, southerly
steering flow, will make for a continued active pattern this
weekend and into next week. The only day-to-day variation will be
how much instability is either limited due to cloud cover and
prior-day rainfall, or not limited, due to a sunnier start and
drier soils. Either way, we are in a pattern where any convection
that does form will have the potential to produce above average
rainfall rates and Flash Flooding, especially due to frequently
saturated soil over much of the area.

A Flash Flood Watch has already been issued for much of the area
and we expect more of the same in the coming days. This is truly
quite a prolific pattern and extended further to the west and
northwest than we have seen in a few years. Stay safe out there.

&&

AVIATION...For the 18Z TAF package...Expect scattered to numerous
thunderstorms along and south of a KSJN-KINW-KGCN through 03Z.
Activity will be more in the isolated to scattered range northeast
of that line. After 03Z, shower and storm activity becoming
isolated. Surface winds light away from storms. Aviation discussion
not updated for TAF amendments.

&&

FIRE WEATHER...Widespread showers and storms will continue through
the weekend with peak activity in the afternoons. Expect gusty and
erratic winds near any storms. Flash flooding remains possible.
Otherwise, light winds away from storms with little change in high
and low temperatures.

Monday through Wednesday...Little change. Monsoon moisture will
remain in place with showers and thunderstorm each day.

&&

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Flood Watch through this evening for AZZ004>008-012>018-037-038-
104>108-112>118-137-138.

&&

PUBLIC...BJ
AVIATION...McCollum
FIRE WEATHER...McCollum

For Northern Arizona weather information visit
weather.gov/flagstaff