132
FXUS65 KFGZ 131119
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
419 AM MST Sun Sep 13 2026

.SYNOPSIS...Daily afternoon and evening thunderstorm chances will
occur throughout this week. Temperatures will be close to mid
September averages with occasional southwesterly breezes in the
afternoon hours.

&&

.DISCUSSION...The main story this week will be the passage of
multiple shortwaves interacting with monsoon moisture that remains
across the state. The first will arrive this afternoon as an
upper level Low traveling along the northern Tier trails a wave
across the state. Expect thunderstorm coverage to increase today
with individual storm motion moving off to the northeast. The
highest POPs favor the western zones today, with the best POPs
moving into the eastern zones on Monday as the wave pushes east.

Starting on Tuesday a trough deepens off the West Coast. Another
wave off this trough approaches Tuesday night through Wednesday
morning. This will be followed by another wave Thursday into
Friday. Each of these waves will keep the daily shower and
thunderstorm chances going. This last wave moving out on Saturday
morning may potentially bring some drier air into the area which
could confine precipitation chances to the far eastern part of the
state or push the precipitation all the way into the New Mexico
but we`ll have to keep monitoring to see if that`s the case.

&&

.AVIATION...Sunday 13/12Z through Monday 14/12Z...Mainly VFR
conditions, brief MVFR conditions possible near stronger storms.
Expect scattered showers and thunderstorms to develop between
18Z-03Z, best chances generally west of a KPGA-KPAN line. Daytime
winds S-SW 10-20kts, light and variable or terrain driven
overnight. Gusty and erratic winds possible near thunderstorms.

OUTLOOK...Monday 14/12Z through Wednesday 16/12Z...Mainly VFR,
brief MVFR possible near stronger storms. Scattered to numerous
showers and thunderstorms likely during the afternoon and evening
hours, with some nighttime showers and storms possible Monday
night into Tuesday morning and Tuesday night into Wednesday
morning. Highest coverage of storms will favor areas east of I-17
and US-89. Winds S-SW 10-20kts daytime, light and variable or
terrain driven overnight. Gusty and erratic winds possible near
thunderstorms.

&&

.FIRE WEATHER...Today through Monday...Scattered showers/storms
coverage more widespread over the next couple days. Storms will be
capable of producing heavy rain, hail, frequent lightning, and
gusty/erratic winds. Daytime winds S-SW 10-20 mph gusting up to 25
mph. Minimum RH values generally between 30-55% each afternoon.

Tuesday through Thursday...Daily chances for showers/thunderstorms
will continue each afternoon/evening. Coverage of storms may vary
each day depending on previous day`s activity. Storms will be
capable of producing heavy rain, hail, frequent lightning, and
gusty/erratic winds. Daytime winds S-SW 10-20 mph. Minimum RH values
generally between 30-60% each afternoon.

&&

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

&&

$$

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

For Northern Arizona weather information visit
weather.gov/flagstaff