877 
FXUS65 KFGZ 181719
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1019 AM MST Sat Apr 18 2020

.SYNOPSIS...A series of weather disturbances will deliver
unsettled conditions to northern Arizona through the middle of
next week. The best chances for showers will come this afternoon
into the evening and again on Tuesday. Daytime temperatures will
remain a bit below normal with the coolest days today and Tuesday.
Expect breezy conditions each afternoon.

&&

.UPDATE...We made a minor update to the forecast grids to 
slightly increase thunder probabilities this afternoon, and also 
to refine precip chances through this evening. The forecast is on 
track.

&&

.PREV DISCUSSION /256 AM MST/...The forecast for a series of
weather disturbances and unsettled weather over the coming days
across northern Arizona still holds. Scattered showers and even a
few thunderstorms observed overnight across west to northwest
Arizona were induced by the passage of the first in a pair of
shortwave troughs. This first disturbance will move out of Arizona
this morning with showers ending by sunrise. However, a secondary
disturbance will rapidly take its place this afternoon and 
evening. It's still looking like an area of scattered showers will
develop from about Interstate-40 northward this afternoon lasting
into the evening. In addition, instability will increase with 
daytime heating with the development of a few thunderstorms across
the area. The core of this second shortwave will essentially be 
overhead today resulting high temperatures 4 to 7 degrees lower 
than on Friday.

For Sunday and Monday...A break in systems is expected with
warmer temperatures and afternoon southwest breezes in the 10 to
20 mph range. Any decent precipitation threat will not arrive
until Monday night.

On Tuesday and Wednesday...The next in the series of shortwave
troughs will move across Arizona. The Tuesday/Wednesday trough
still looks more vigorous with a decent shot at scattered showers
from around Interstate-40 northward. The cold pool and moisture
associated with this system will even produce an isolated
thunderstorm or two Tuesday afternoon and evening. Otherwise,
cooler and breezy.

From Thursday onward...The unsettled weather pattern continues on
Thursday or Friday with another chance of precipitation. Models
are consistent in building high pressure over the southwest United
States next weekend. We'll see.

&&

.AVIATION...For the 18Z Package...Scattered -SHRA with isolated
-TSRA expected this afternoon and evening, with the greatest
 coverage near and north of a KFLG to KRQE line. Brief MVFR
 conditions and erratic/gusty winds possible in showers. Aviation
 discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Expect breezy afternoon winds this weekend. 
Isolated to scattered showers and a few thunderstorms are possible 
this afternoon and evening. Drier and warmer weather returns Sunday.

.Monday through Wednesday...Dry weather Monday will yield to 
increasing chances for showers and a few thunderstorms on 
Tuesday. Wednesday will see a return of drier weather.

&&

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

&&

$$

PUBLIC...AT/McCollum
AVIATION...AT
FIRE WEATHER...AT/NL


For Northern Arizona weather information visit
weather.gov/flagstaff