372
FXUS65 KFGZ 040929
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
229 AM MST Tue Jun 4 2024

.SYNOPSIS...Hotter temperatures and mainly dry conditions are
expected this week 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...Mid and high level clouds continue to rotate
southward into our region around the developing high off the west
coast. Expect to see these clouds off and on through most of the
day before clearing out this evening. Temperatures will be a few
degrees warmer than Monday topping out 3-7 degrees above average
for early June. Daytime temperatures will continue to heat up
Wednesday through Friday as the high shifts eastward over Arizona
and New Mexico. 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). One factor that could possibly
keep high country temperatures from reaching the full potential
beginning Thursday is some increased moisture leading to cumulus cloud
cover during peak heating hours. The moisture is being drawn
northward around the high center that will be just to our east.
We added a slight chance for a high-based (mainly dry) thunderstorm
to the forecast for the White Mtns and rim country up to Grand
Canyon for Thursday afternoon. Again, gusty winds could accompany
any showers/storms but any rainfall would be very light. This
continues Friday but should shift to mainly eastern Arizona. By
the weekend - heights are forecast to drop slightly as a weak low
drifts northward from Mexico. Temperatures come down a few
degrees each day. Right now the plan is to end the Excessive Heat
Warning on Friday evening but we will need to monitor the northern
zones that are included (Grand/Marble/Glen Canyons) as there is a
chance these would need extended to Saturday. Otherwise, limited
moisture lingers over the weekend into Monday, with low chances
for a shower or thunderstorm (10-20%).

&&

.AVIATION...Tuesday 04/06Z through Wednesday 05/06Z...VFR conditions
with W/NW winds 10-15 kts with gusts to around 20 kts during
daylight hours, becoming light and variable for the overnight.

OUTLOOK...Wednesday 05/06Z through Friday 07/06Z...VFR conditions
with winds generally 10 kts or less.

&&

.FIRE WEATHER...Tuesday and Wednesday...Warming temperatures and
mostly dry conditions expected to continue. Minimum RH values
forecast between 5-20% each afternoon, with overnight recoveries
varying between 25-60%. Look for west-northwest 5-15 mph today,
becoming variable around 10 mph or less on Wednesday.

Thursday through Saturday...Hot temperatures and mostly dry
conditions will continue, except for a slight potential for dry
thunderstorms. Minimum RH values generally 15% or less, with
overnight recoveries around 25-50%. Expect west-southwest winds 5-15
mph each afternoon.

&&

.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...Humphreys
FIRE WEATHER...Konieczny

For Northern Arizona weather information visit
weather.gov/flagstaff