945
FXUS65 KFGZ 071031
AFDFGZ
Area Forecast Discussion
National Weather Service Flagstaff AZ
331 AM MST Mon Jul 7 2025
.SYNOPSIS...Hot temperatures and mainly dry conditions are
expected this week. There will be a slight chance of showers and
thunderstorms each afternoon, with most of the activity over the
Mogollon Rim and White Mountains. Temperatures will peak from
Tuesday through Thursday, with very hot conditions at the lower
elevations.
&&
.DISCUSSION...Strong high pressure was centered near southeast
Arizona this morning, with a closed low off the central California
coast. The resulting southerly flow has allowed for some limited
moisture to return to our area, though these values are on the low
end for monsoon season. Expecting isolated to scattered high-based
convection to develop this afternoon, with the highest coverage
over the Mogollon Rim/White Mtns (20-40%) and a few showers or
storms possible as far west as Prescott. Storm motion will be
toward the northeast, so activity over the Rim/White Mtns will
push into the Little Colorado River Valley so places like Winslow,
Holbrook, and St Johns also have a 20-30% chance of seeing some
light rain but also gusty outflow winds to 40+ mph. On Tuesday,
some of this moisture gets into western Coconino County so the
focus for isolated storms looks to be Flagstaff westward, including
the Prescott area where a 10-25% chance of showers/storms is
forecast. However, the main story over the next several days is
going to be the building heat wave. The center of high pressure
will continue to gradually shift northwestward and be right over
central Arizona by Wednesday. It is then forecast to drift south
and west by late in the week and weekend, reaching southern
California. In addition to bringing heat to our area, the
resulting flow as the high shifts south/west will mostly cut off
our moisture and lead to a further downturn in storm chances.
Extreme Heat Warnings go into effect for the Grand Canyon below
4000 feet today and continue through Thursday, with a good chance
this will need to be extended to Friday and possibly beyond.
There is also an Extreme Heat Warning for Yavapai and Gila
counties below 4000 feet on Wednesday when the heat is forecast to
peak.
&&
.AVIATION...Monday 07/12Z through Tuesday 08/12Z...VFR conditions.
Isolated -SHRA/-TSRA possible south of a KGCN-KRQE line between
18Z and 03Z. Winds light and variable or terrain driven overnight,
SW 5-15 kts, gusts 20-25 kts during the day, light and variable
or terrain driven Monday night. Winds may be gusty and erratic
around thunderstorms.
OUTLOOK...Tuesday 08/12Z through Thursday 10/12Z...VFR conditions.
Isolated -SHRA/-TSRA possible south of a KGCN-KSJN line between
18Z and 03Z each day. Winds SW-W 5-15 kts, gusts 15-20 kts during
the day, light and variable or terrain driven overnight.
&&
.FIRE WEATHER...Today and Tuesday...Hot and mainly dry conditions.
Slight chance of showers and thunderstorms each afternoon, mainly
over higher terrain. Winds west/southwest 5-15 mph with gusts up to
20 mph each afternoon with minimum afternoon RH 10-20%. Gusty
erratic outflow winds possible near thunderstorms.
Wednesday through Friday...Hot and mainly dry conditions continue,
outside of a slight chance of showers and thunderstorms mainly near
the White Mountains each afternoon. West winds 5-15 mph Wednesday,
then west/southwest 10-15 mph with gusts 20-30 mph Thursday and
Friday. Minimum afternoon RH 8-20%.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning from 10 AM this morning to 8 PM MST
Thursday for AZZ006.
Extreme Heat Warning from 10 AM to 8 PM MST Wednesday for AZZ018-
037.
&&
$$
PUBLIC...JJ
AVIATION...JJ
FIRE WEATHER...JJ
For Northern Arizona weather information visit
weather.gov/flagstaff
NWS Flagstaff Office
Tucson, AZ 
