187
FXUS65 KFGZ 050926
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
226 AM MST Wed Jun 5 2024

.SYNOPSIS...Hotter temperatures and mainly dry conditions are
expected through Friday as high pressure builds over the
Southwest. Temperatures begin to cool gradually for this weekend
with the potential for a few showers and thunderstorms.

&&

.DISCUSSION...Clear skies and light winds were observed over
northern Arizona early this morning. Temperatures were relatively
mild at 2 AM - in the 50s/60s at higher elevations and 70s for the
valleys. For today - strong high pressure will shift eastward and
be centered over northern Arizona this afternoon. The center of
high pressure will then move into NM/TX by Thursday and Friday.
Daytime temperatures will continue to heat up today through
Friday. The hottest days still look like Thursday and Friday when
highs are 10-15 degrees above average. Forecasts highs are
105-111 below 4000 feet for the Grand Canyon, Marble/Glen Canyons,
and Yavapai County/Verde Valley. An Excessive Heat Warning
remains in effect Thu/Fri in these areas. It will be hot elsewhere
too, near 90 along the Mogollon Rim/Flagstaff, upper 90s for
Prescott/Payson, to 100-104 in the Little Colorado River Valley
including Winslow. If Flagstaff reaches the forecast high of 90 on
Thursday, it will tie for the earliest occurrence of 90 degrees
on record (June 6, 2010). As the high shifts eastward, southerly
flow will pull some increased mid level moisture into the region,
with afternoon cumulus development over the higher terrain. Hi-res
models also continue to show some weak convection over the
Mogollon Rim/White Mtns possibly up to the Grand Canyon for
Thursday afternoon at peak heating. We continued the slight chance
for a high-based (mainly dry) thunderstorm in the forecast for
these areas. Again, gusty winds to 30-40 mph could accompany any
showers/storms but any rainfall would be very light. Isolated
lightning strikes will pose a risk for wildfire starts. This
continues Friday but should shift to mainly eastern Arizona with
somewhat drier air over central/western AZ. For the weekend into
Monday - heights are forecast to drop slightly as a weak low
drifts northward from Mexico. Temperatures come down a few degrees
each day dropping to near normal Sun/Mon. Otherwise, limited
moisture lingers, with low chances for a shower or thunderstorm
(10-20%).

&&

.AVIATION...Wednesday 05/06Z through Thursday 06/06Z...VFR
conditions will persist. Look for light and variable winds
generally less than 10 kts.

OUTLOOK...Thursday 06/06Z through Saturday 08/06Z...VFR
conditions are forecast. Afternoon winds west to
southwest at 5-15 kts with gusts as high as 25 kts on Friday.
Isolated thunderstorms possible Thursday along a KGCN-KFLG-KJTC
during the afternoon and evening. Storm threat shifting eastward
on Friday to mainly along and south of a KSOW-KSJN line.

&&

.FIRE WEATHER...Wednesday and Thursday...Hot temperatures both
afternoons, with a slight chance for showers/thunderstorms across
higher terrain on Thursday. Variable winds generally less than 15
mph today, becoming southwest on Thursday. Look for minimum RH
values between 5-15%.

Friday through Sunday...Temperatures will gradually cool through the
weekend, with slight chances for showers/thunderstorms each
afternoon, mostly near the White Mountains. Look for daily west-
southwest winds 10-20 mph. Minimum RH values will generally below
15% Friday and Saturday, increasing slightly on Sunday.

&&

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

&&

$$

PUBLIC...JJ
AVIATION...McCollum
FIRE WEATHER...Konieczny

For Northern Arizona weather information visit
weather.gov/flagstaff