748
FXUS65 KFGZ 261724
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1024 AM MST Thu Jun 26 2025

.SYNOPSIS...Warming temperatures and mainly dry conditions
continue through the weekend, outside of light afternoon showers
around the White Mountains. More widespread shower and thunderstorm
activity looks to set in by the middle of next week.

&&

.DISCUSSION...Today...The trough that has been situated to the
west begins to lift and weaken today. Southwesterly flow looks to
usher in drier air across much of the area, outside of some
lingering moisture across the White Mountains. Thus, dry and
warmer conditions are expected again today, with only a slight
chance for high-based showers and possibly a thunderstorm around
the White Mountains this afternoon.

Friday through Monday...Heights begin to rise for the end of the
week and into next week as high pressure starts to build over the
southwest. Temperatures look to begin to rise over the weekend and
into early next week, ushering in a return of more seasonable to
slight above normal temperatures. Some heat headlines may be needed
for the lower elevations of the Grand Canyon over the weekend as
highs look to exceed 110F by Sunday. Dry conditions look to prevail
each day as well, with mainly only a slight chance for high-based
showers over the White Mountains each afternoon. A bit more activity
could be possible during the afternoon Monday, depending on how much
moisture is able to be advected northward at this point.

Tuesday onward...Another weak trough looks to setup just off the
California coast near the start of next week. While at the same
time, a potential tropical system passes just off the tip of the
Baja California peninsula, potentially driving a surge of moisture
northward along the Gulf of California. With the increased southerly
flow over Arizona, this plume of sub-tropical moisture is expected
to be advected northward into Arizona. Thus, daily chances for
showers and thunderstorms are expected over much of the higher
terrain starting as early as Tuesday and continuing through the rest
of the week. The onset of the monsoon appears to be upon us!

&&

.AVIATION...Thursday 26/18Z through Friday 27/18Z...VFR conditions
expected, only precipitation chances are a few isolated high based
thunderstorms over the White Mountains during the afternoon hours.
Winds SW 10-15kts, gusts to 20kts during the day, light and
variable or terrain driven overnight.

OUTLOOK...Friday 27/18Z through Sunday 29/18Z...VFR conditions
expected, only precipitation chances are a few isolated high based
thunderstorms over the White Mountains on Friday afternoon. Winds
SW-W 5-15kts, gusts to 20kts each day, light and variable or
terrain driven overnight.

&&

.FIRE WEATHER...Today and Friday...Mainly dry and warm conditions,
outside of a slight chance for high-based showers and thunderstorms
near the White Mountains each afternoon. Winds southwest 5-15 mph
with gusts to around 20 mph each afternoon. Gusty, erratic winds
possible in and around thunderstorms.

Saturday through Monday...Warmer and mainly dry conditions. Wind
west/southwest winds 5-15 mph and afternoon minimum RH values 5-15%
each day.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

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

For Northern Arizona weather information visit
weather.gov/flagstaff