559
FXUS65 KFGZ 111030
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
330 AM MST Tue Jun 11 2024

.SYNOPSIS...High pressure will build and strengthen over Arizona,
leading to hot temperatures across the region for the middle of
the week. Cooler, more seasonable temperatures return to finish
out the week, along with a chance for showers and thunderstorms
later Thursday into Friday.

&&

.UPDATE...Isolated showers have ended near the New Mexico border
this evening with sky cover clearing overnight. Tranquil weather
conditions are expected for tonight with little to no wind and
near average temperatures. High pressure begins to develop over
much of the West tomorrow, resulting in increasing temperatures.
Afternoon breezes will remain on the lighter side, 10-20 mph, for
tomorrow along with persistent dry conditions. The heat will only
get worse for Wednesday and Thursday as high pressure strengthens.
The current Excessive Heat Warning for our lower valleys/canyons
for Wednesday and Thursday looks good with no changes needed.
Besides for a few tweaks to the low temperatures tonight, the
forecast remains on track.

&&

.PREV DISCUSSION /510 PM MST/...Weak low pressure over New Mexico
continues to keep northeast Arizona partly to mostly cloudy this
afternoon. Modest low level moisture (dewpoints near 40F) will
bring a few isolated light showers this afternoon during peak
heating, mainly near the Chuska Mountains. Elsewhere, near normal
temperatures and mostly sunny skies prevail.

Tuesday and Wednesday - high pressure centered over northern
Mexico will strengthen and extend northward into Arizona.
Afternoon high temperatures will increase accordingly, reaching
near 10 degrees above climatological averages Tuesday then 10-15
degrees above for Wednesday. The Excessive Heat Warning for areas
below 4000 feet beginning Wednesday looks good. A closed low off
the coast of northern Baja will begin to shift eastward by
Wednesday with an increase in wind speeds in western Arizona with
gusts 25-30 mph.

Thursday and Friday - there is good model agreement that the
closed low off the coast will move northeastward toward western
Arizona Thursday, then cross the state Thursday night and Friday.
Gradients out ahead of the low increase and will lead to more
widespread gusty southwest winds Thursday, becoming more westerly
and shifting to mainly eastern Arizona for Friday. Preliminary
speeds of 15-25 mph with gusts 25-35 mph are forecast. This will
bring some elevated fire weather concerns as humidity remains low.
The Excessive Heat Warning below 4000 feet continues through
Thursday. As the low moves across the area, it will bring some
mainly mid level moisture with it, leading to a chance of high-
based showers Thursday evening. By Friday, the best chance
(20-40%) for high-based showers and thunderstorms shifts to areas
mainly northeast of the Mogollon Rim. There will be a threat of
dry lightning and some new fire starts, again mainly northeast AZ.

Saturday and Sunday - the closed low moves well east of Arizona as
a larger trough takes shape over the northwest US. Dry weather
returns with breezy southwest winds. Temperatures a few degrees
above normal.

&&

.AVIATION...Tuesday 11/12Z through Wednesday 12/12Z...VFR
conditions with W/SW winds 5-10 kts, becoming light and variable
after 02Z.

OUTLOOK...Wednesday 12/12Z through Friday 14/12Z...VFR conditions,
outside of brief periods of MVFR in -SHRA/-TSRA after 00Z Friday.
Gusty, erratic winds possible near TS. Winds W/SW 10-15 kts with
gusts 20-25 kts each afternoon.

&&

.FIRE WEATHER...Today and Wednesday...Dry conditions with hot
temperatures, along with afternoon RH values 5-15%. West/southwest
winds 10 mph or less, becoming southwest 10-15 mph with gusts up to
25 mph on Wednesday.

Thursday through Saturday...Hot conditions remain on Thursday,
before cooling slightly. Breezy west/southwest winds with gusts of
20-30 mph possible each afternoon. Chance for isolated high-based
showers and thunderstorms late Thursday and Friday, especially along
and north of the Mogollon Rim. Dry conditions are otherwise expected.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning from 10 AM MST /11 AM MDT/ Wednesday to 8
PM MST /9 PM MDT/ Thursday for AZZ005-006-037.

&&

$$

PUBLIC...LaGuardia/JJ
AVIATION...Humphreys
FIRE WEATHER...Humphreys

For Northern Arizona weather information visit
weather.gov/flagstaff