406
FXUS65 KFGZ 080956
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
256 AM MST Wed Oct 8 2025

.SYNOPSIS...Warm and mainly dry conditions continue today, with a
few showers or thunderstorms in eastern Arizona. Widespread rain
and thunderstorms then spreads into the region from Thursday
through Saturday, with areas of heavy rain likely. Some flash
flooding will be possible, especially late Friday into Saturday. A
few showers may continue into early next week.

&&

.DISCUSSION...It`s a clear and chilly morning around northern
Arizona with surface dewpoints still in the 20s for most areas. A
high pressure ridge stretches across the southern US, expanding
slightly westward today. At the same time, an upper low is diving
down the west coast. These two features will bring an increase in
south-southwesterly flow over Arizona for the next few days,
opening the door for a rapid increase in atmospheric moisture. The
initial moisture increase will occur today, with isolated to
scattered showers and thunderstorms developing in east central
Arizona, spreading westward through the evening and overnight. A
more significant surge in moisture will occur Thursday, as remnant
moisture from the weakening tropical cyclone Priscilla gets
entrained into the flow and pulled into the state. HREF mean
precipitable water values climb to around 1.00" on the Mogollon
Rim to 1.50" over the lower elevation of Yavapai County by mid
day. Widespread rain with isolated thunderstorms are forecast to
develop by Thursday morning and continue off and on through
Saturday. Rainfall rates on Thursday look to be low enough that
the risk of flooding is low. By Friday and especially Friday
night/Saturday, rainfall rates should increase due to the approach
of the upper level trough from the west. WPC has placed areas NW
of a Payson to four corners line in a Slight Risk for excessive
rainfall on Friday, expanding to include all of northern/central
Arizona for Saturday. Flood Watches may be needed for portions of
northern/central Arizona from Friday into Saturday - these will be
collaborated with neighboring offices and possibly issued in the
next 12-24 hours. Forecast rainfall totals from Thursday through
Sunday are mostly in the 1-3" range over central and northern AZ,
with lower amounts in east central portions of the state where the
moisture plume is later to arrive. The higher end scenarios (10%
chance of occurring) are closer to 4" so this system definitely
has the potential for some impressive rainfall and flooding
impacts. The most likely areas for this to occur are from the
Mogollon Rim to the mountains of Yavapai County, but there is
still uncertainty in exactly where the heaviest rain bands will
set up. With increasing wind shear later Friday into Saturday, a
few strong thunderstorms could also develop, but the limiting
factor looks to be weak instability and cool surface temperatures.

Sunday through Tuesday - as the trough moves eastward, another one
develops over the Pac NW and keeps our area in southwesterly flow.
The deep moisture plume is forecast to shift south and east of our
area by Sunday afternoon with lowering precip chances. There is a
10-30% chance of showers Monday and Tuesday, but the deeper
moisture from another tropical system is currently forecast to
remain southeast of our forecast area.

&&

.AVIATION...Wednesday 08/06Z through Thursday 09/06Z...VFR expected.
Daytime S-SW winds 5-15 kts with gusts to 25 kts, becoming light
and variable during the overnight period.

OUTLOOK...Thursday 09/06Z through Saturday 11/06Z...Mainly VFR
expected. ISO-SCT SHRA/TSRA after 12Z/Thu with periods of MVFR or
lower possible with gusty/erratic winds. Expect daytime SE-SW winds
10-20 kts, becoming lighter 5-15 kts during the overnight period.

&&

.FIRE WEATHER...Today and Thursday...Mild and mainly dry conditions
today, outside of a slight chance for showers and thunderstorms
across eastern Arizona. Cooler, and wetter conditions set in for
Thursday with wetting rains expected. Winds south/southwest 5-15 mph
today, becoming south/southeast on Thursday.

Friday through Sunday...Turning cooler. Wetting rains likely with
widespread showers and thunderstorms both Friday and Saturday.
Isolated to scattered storms will remain on Sunday. Daytime winds
south/southeast 5-15 mph on Friday, becoming southwest 10-15 mph
over the weekend.

&&

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

&&

$$

PUBLIC...JJ
AVIATION...Meola
FIRE WEATHER...Humphreys

For Northern Arizona weather information visit
weather.gov/flagstaff