683
FXUS65 KFGZ 190452
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
952 PM MST Wed Jun 18 2025

.SYNOPSIS...Hot and dry conditions expected through the weekend.
Winds increase Thursday with an incoming trough, peaking on
Friday- Saturday before gradually decreasing. Several days of
Near- Critical to Critical fire weather concerns by the end of the
week. Precipitation chances gradually increase from the southeast
early next week.

&&

.DISCUSSION...High pressure takes hold once again today as a shallow
shortwave trough exits the region. A very dry airmass and subsidence
under the ridge is keeping skies mostly cloud free today. Heights at
500mb return to above climatological averages, and daytime highs
will be few degrees warmer than yesterday. Temperatures will remain
above average through Friday, and an Extreme Heat Warning remains in
effect below 4000` in the Grand Canyon. Winds are light today on
account of weak synoptic flow, but this will not last long.

A trough is evident in mid-level WV imagery, currently located off
the coast of Washington/Oregon. This feature will dig southward
and tighten the pressure gradient over northern AZ, bringing
elevated wind gusts out of the south-southwest at 25-35 mph to the
region as soon as Thursday afternoon. The trough becomes situated
over the western US on Friday, then remains relatively stationary
through early next week. The strongest winds are expected on
Friday-Saturday, generally out of the southwest with wind gusts
over 40 mph. After Saturday, the trough begins to weaken in
intensity allowing the pressure gradient to relax over northern
AZ. Winds stay breezy, but decrease in magnitude each afternoon
through the middle of next week. With a mostly dry airmass
remaining in place, these winds will usher in several days of
repeated Near-Critical to Critical fire weather concerns. A Fire
Weather Watch has been issued for Friday and Saturday, see the
fire discussion below for more details.

Precipitation chances are initially low with this setup. Tropical
moisture will surge northward under the trough-ridge pattern,
however the positioning of the synoptic features will keep the
majority of moisture to our east. Nevertheless, a steady rise in
dewpoints can still be expected each day (not enough to dispel fire
weather concerns), and mentionable precipitation chances begin to
encroach from the southeast next week. With how far out this signal
is, confidence is still low. However this is something to keep
watching as the forecast evolves.

&&

.AVIATION...Thursday 19/06Z through Friday 20/06Z...VFR conditions
with VRB winds 5-10 kts overnight, becoming S/SW 10-20 kts after 18Z.

OUTLOOK...Friday 20/06Z through Sunday 22/06Z...VFR conditions.
Daytime winds S/SW 15-25 kts with gusts 25-35 kts, subsiding to 5-15
kts during the overnight.

&&

.FIRE WEATHER...Thursday and Friday...One more day of hot
temperatures on Thursday with a cooling trend beginning on Friday.
It remains dry with minimum RH values both days at 5-10%. Winds
increase to SW 15-25 mph with gusts near 35 mph Thursday and
intensify more Friday with winds SW 20-30 mph, gusting to 40 mph.
Near critical fire conditions possible Thursday, with critical fire
weather conditions likely Friday with a Fire Weather Watch in
effect starting Friday morning.

Saturday through Monday...A cooling trend continues on Saturday but
it will remain dry and windy with RH values 5-15% and SW winds 20-30
mph, gusting to 40 mph.  A Fire Weather Watch continues into
Saturday evening.  By Sunday and Monday temperatures will be about 5
degrees below average and min RH will be at 10-20%.  Winds continue
to be SW 15-20 mph, gusts 25 to 30 mph.  Areas of critical fire
weather will still be found but won`t be as widespread as on
Saturday.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 7 PM MST Friday for AZZ006.

Fire Weather Watch from Friday morning through Saturday evening
for AZZ107>117-139-140.

&&

$$

PUBLIC...Lewandowski
AVIATION...Humphreys
FIRE WEATHER...Bernhart

For Northern Arizona weather information visit
weather.gov/flagstaff