924 
FXUS65 KFGZ 181010
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
310 AM MST Wed May 18 2022

.SYNOPSIS...Warm and dry conditions will continue through Thursday.
Critical fire weather conditions will become possible on both 
Thursday and Friday as winds increase. Relatively cooler daytime 
temperatures begin Friday and last into the weekend before warming
up again next week.

&&

.DISCUSSION...A weak closed low will pass from southern California
into northern Mexico today, with high pressure remaining over
northern Arizona. It will be another warm day with highs close to
10 degrees above seasonal averages. With deep mixing and slightly
more boundary layer moisture today, we will likely see some
afternoon cloud buildups over the higher terrain and maybe even
some virga. 

Thursday and Friday - a trough will shift southward toward the
region from the north with a significant increase in winds. For
Thursday, the windiest area is expected to be mostly north of 
I-40 and a Red Flag Warning has been issued as winds combine with
low humidity. On Friday, as the trough sags farther south,
temperatures will cool 5-10 degrees and southwest winds will be
stronger. Currently expecting sustained winds of 20-30 mph with
gusts 35-45 mph. A Fire Weather Watch has been issued for the
majority of northern Arizona for Friday. Humidity will be up a bit
due to the cooler temperatures and slightly higher dewpoints, so
portions of the watch may have to be cancelled if it looks like we
won't reach the RH thresholds - so stay tuned. May also need a 
Wind Advisory for Friday but will address that as we get a bit 
closer.

Cooler daytime temperatures near seasonal averages should stick
around for the weekend as we continue to be influenced by the
trough to the north. This will also keep it breezy, but wind
speeds should be lower than Friday. Looking farther ahead, some
model spread for Monday with about 60% of solutions in the WPC
Cluster tool indicating the trough lingering and 40% building a
ridge. Good agreement Tuesday and beyond in ridging and a return
to well above normal temperatures.

&&

.AVIATION...For the 12Z TAF package...VFR conditions will continue 
through the TAF period. Light winds will become southwest winds 10 
to 20 knots with gusts 20 to 30 knots after 17Z then decrease again 
after 03Z. Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...On Wednesday, expect above normal temperatures, 
light winds and afternoon humidity in the teens to single digits. A 
Red Flag Warning has been issued for Thursday due to critical fire 
weather conditions caused by low humidity and strong southwest 
winds for north of the Mogollon Rim.

Friday through Sunday....Another round of critical fire weather 
conditions is possible Friday. Due to this, a Fire Weather Watch has 
been issued for most of Northern Arizona. Very dry and breezy 
conditions continue on Saturday and Sunday.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...Fire Weather Watch from 
Friday morning through Friday evening FOR AZZ104>117-138>140.

Red Flag Warning from 11 AM to 9 PM MST Thursday FOR AZZ104>107-
109>114-139-140.

&&

$$

PUBLIC...JJ
AVIATION...Kobold
FIRE WEATHER...Kobold

For Northern Arizona weather information visit
weather.gov/flagstaff