Flash Flood Warning 16, NWS Flagstaff, AZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
908 PM MST Sat Aug 29 2020

.SYNOPSIS...Shower and thunderstorm chances will increase through
Sunday. There will be a threat for heavy rain across Yavapai and
Gila counties where a Flash Flood Watch is in effect through
Sunday evening. Expect decreasing thunderstorm chances from
Tuesday of next week onward with warmer weather returning by the
end of the week.

&&

.DISCUSSION...
Just a few generally light showers are continuing across northern
AZ this evening. However, more significant moisture across
southern AZ will continue to push northward tonight and especially
Sunday with showers forecast to increase. The focus for the
precipitation is still expected to be along Gila and Yavapai
counties.

&&

.PREV DISCUSSION /239 PM MST/...Moisture continues to increase,
especially across southern and into central parts of the state.
The increased moisture and associated instability will be greatest
for areas south of the rim across Yavapai and Gila counties where
a Flash Flood Watch is in effect. The overall trend in forecast
model data today suggests the greatest coverage of storms and
heavy rain potential has shifted a bit later to Sunday. We have
adjusted the forecast trends and precip chances to reflect this.
Anyone with outdoor plans this weekend (especially south of the
Mogollon Rim) should monitor the weather and have a good way to
receive warnings.

The chance for storms will continue into early next week but favor
areas where the deeper moisture resides, generally along and south
of the rim and White Mountains. A trough is forecast to move
through the four corners region on Tuesday bringing an increase in
wind speeds, followed by a drying trend. Drier weather is
expected through the rest of the week as a strong ridge of high
pressure building in from the west takes hold of the weather
pattern. Not an unfamiliar pattern this year. In addition to the
dry trend, we can expect temperatures to rise again by the end of
the week becoming quite warm for early September.

&&

.AVIATION...For the 06Z package...Widespread showers and storms
are expected to develop Sunday and last through much of the day.
Expect areas of MVFR/IFR and local +RA through the day, decreasing
Sunday evening. Aviation discussion not updated for TAF
amendments.

&&

.FIRE WEATHER...Expect scattered showers and thunderstorms through
Monday across northern Arizona, with the best chance of wetting
rain along and south of the Mogollon Rim on Sunday. Look for light
winds except gusty near storms. Temperatures will be several
degrees cooler.

Tuesday through Thursday...Precipitation chances will decrease
Tuesday as a drier northwest flow develops. Dry conditions are
likely through the week with temperatures warming above average
again by the week's end.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...Flash Flood Watch through
Sunday evening FOR AZZ008-018-037.

&&

PUBLIC...KD/MCT
AVIATION...KD
FIRE WEATHER...MCT

For Northern Arizona weather information visit
weather.gov/flagstaff