503 
FXUS65 KFGZ 061628
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
928 AM MST Tue Aug 6 2019

.SYNOPSIS...Monsoon moisture will remain in place through Thursday
with a chance of showers and thunderstorms each day. Look for
seasonal temperatures with mainly light winds outside of
thunderstorms. Some drying is expected across western Arizona from
Friday through the weekend.

&&

.UPDATE...No significant changes to the forecast this morning as
cloud cover over most of the area will delay heating and
subsequent convection. Some erosion of the cloud shield from the 
east is already occurring, allowing for an earlier initiation of 
storms over the higher terrain near the New Mexico border, and 
moving westward through the late morning and afternoon hours. 

&&

.PREV DISCUSSION /338 AM MST/...High pressure in the mid-levels
remained centered over Arizona and New Mexico this morning. We
are still expecting an eastward shift of the high center over the
coming days which will eventually lead to some drying heading
into the weekend.

Looking at today...High pressure will wobble over Arizona and New
Mexico with monsoon moisture remaining in place. The position of
the high is placing south to southeast flow across the area
allowing the moisture from a dying thunderstorm complex over
northwest Mexico to stream across Arizona. Along with this
moisture will be ample cloudiness which will inhibit thunderstorm
development to some degree. However, we think there will be
enough breaks in the clouds for some instability and thunderstorm
development. The best chances will be along the Mogollon Rim and
over the White Mountains. Storms will tend to be pushed to the
north by the flow aloft and could make their way across the
Little Colorado River Valley during the afternoon. With higher
moisture levels and light winds localized heavy rain and flash
flooding are the main threats. Otherwise, cooler temperatures with
generally light winds.

For Wednesday and Thursday...As high pressure slowly moves
eastward the flow will remain from the south to southeast with
ample monsoon moisture moving across Arizona. Any moisture could
be enhanced by additional thunderstorm complexes over northwest
Mexico or southern Arizona. For this reason we are looking for a
good chance for shower and thunderstorm activity through this
period. With more showers, storms and cloud cover daytime highs
will continue on the cool side.

For Friday and the weekend...Models are in better agreement this
morning with a prominent trough over the western United States
delivering a shot of drier air to west and northwest Arizona. We
are looking for a downturn in monsoon activity in those areas.
Further east across the eastern Mogollon Rim and White Mountains
active monsoon conditions are expected to continue.

&&

.AVIATION...For the 18Z package...Expect primarily VFR with isolated 
MVFR conditions near thunderstorms over the next 24 hours. Expect 
scattered to numerous thunderstorm coverage along the Mogollon Rim 
and White Mountains, with more isolated coverage elsewhere. Storm 
coverage diminishes after 03Z Wednesday. Gusty and erratic winds 
possible near thunderstorms. Otherwise expect light surface winds. 
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Daily chances for showers and thunderstorms will 
continue through Wednesday. Winds will generally be light, expect in 
the vicinity of storms. 

.Thursday through Saturday...Moisture will remain in place with 
chances for showers and thunderstorms each day through Friday. 
Moisture may decrease by the weekend for a downturn in storms. 


&&

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

&&

$$

PUBLIC...Suk/McCollum
AVIATION...ET
FIRE WEATHER...RR


For Northern Arizona weather information visit
weather.gov/flagstaff