074 
FXUS65 KFGZ 121625
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
925 AM MST Fri Aug 12 2022

.SYNOPSIS...Daily showers and thunderstorms will continue across
much of northern Arizona through the weekend. Scattered to
widespread thunderstorms are likely each afternoon, with flash
flooding being the main threat.

&&

.UPDATE...Storms are already firing up over the San Francisco 
Peaks this morning, leading to heightened flash flooding fears 
over the area. Expect storms to significantly increase in coverage
today, first over the high country, before spilling over into the
low country. Avoid vulnerable areas, like normally-dry washes, 
slot canyons, drainages, streams, etc. Heavy rainfall may turn
spots like these into raging torrents. 

&&

.PREV DISCUSSION /217 AM MST/...The active monsoon pattern is
expected to continue for the days to come. As a result, another
Flash Flood Watch is in place for 11 AM MST to 11 PM MST Friday.
This watch includes most of our CWA with the exception of the
northeastern portion of our state. This was largely decided based
on model guidance and the Weather Prediction Center Excessive
Rainfall Outlook for Day 1, where there was a slight risk for
northern Arizona. There could be a need for additional Flash Flood
Watches in our CWA past today, but there are none in place at
this time.

Over the weekend...Thunderstorm activity will continue to
dominate during the afternoon hours, primarily thanks to daytime
heating. The late evening/overnight hours will likely remain the
less active portion of each day for the near future. Expect
another few days of above average PW values and high surface
dewpoints as moisture continues to funnel in from the south. At
this time, there are no major indications by models of our monsoon
activity declining for this forecast period.

Beginning of next week...The high pressure system currently
centered over the Oklahoma Panhandle is looking to shift westward
toward the Pacific Northwest. This transition will be caused by a
deepening trough on the east coast. Even with the change in our
synoptic pattern, there will still be a southerly flow aloft,
continuing to move moisture into Arizona.

&&

AVIATION...For the 18Z TAF package..Expect widespread showers and 
thunderstorms into the early evening hours becoming isolated by 
midnight. VFR conditions and light surface winds away from storms. 
Aviation discussion not updated for TAF amendments.

&&

FIRE WEATHER...The active monsoon pattern continues today and 
Saturday with widespread shower and thunderstorm coverage. The main 
threats include flash flooding and gusty, erratic outflow winds. 
Light winds expected outside of storms with little change in 
temperatures. 

Sunday through Tuesday...Daily shower and thunderstorm activity will 
continue. Look for light winds with little change in temperatures.

&&

&&

.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