270
FXUS65 KFGZ 041842
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1142 AM MST Fri Jul 4 2025

.SYNOPSIS...Warming temperatures and mainly dry conditions are
expected through the weekend. Temperatures continue to climb into
next week, along with gradually returning chances for afternoon
showers and thunderstorms.

&&

.DISCUSSION...Today...With a strong capping inversion in place,
convective activity is largely suppressed this afternoon with a
surface high in place over northern Arizona. Seasonably cool
temperatures and typical afternoon breezes will be the main story
as a result. A stray shower can not be totally ruled out across
eastern Arizona, where the cap is not as strong, but any activity
that does form should be minimal.

Saturday and Sunday...High pressure continues to build over New
Mexico over the weekend, while at the same time a cut-off low begins
to set up off the California Coast. This should act to allow for sub-
tropical moisture to stream northward once again, with chances for
showers and thunderstorms returning to the forecast. Activity
initially looks to be limited to mostly the White Mountains on
Saturday, with the subsidence inversion still in place across much
of the region limiting precipitation chances. By Sunday, the
inversion begins to weaken and chances for precipitation increase
across the higher terrain.

Monday through Thursday...As the high continues to wobble and build
across the southwest, moisture begins to gradually increase each
day. As a result, the chances for afternoon showers and
thunderstorms return for next week, especially access the higher
terrain. The most favorable areas on any given day will largely be
dependent upon the the exact positioning of the high (and consequently
the moisture flow). Remnant debris clouds for the previous days
convection will also play a role in coverage. As the cut off low
ejects off the Pacific later in the week, this could also have an
impact by suppressing the high (and moisture) to the south. Model
guidance still seems to be in a disagreement in the exact
positioning of the high, so confidence in precipitation on any given
day remains low at this point. The GFS seems to favor a better
moisture return with a slightly weaker, but more traditional Four
Corners high. While the ECMWF and CMC both favor a strong (nearly
600 dam) ridge over Arizona, keeping drier conditions in place.

Outside of the precipitation chances, expect a return of warmer,
above normal temperatures going into next week. Afternoon highs look
to be in the upper 80s F to lower 90s F across the higher terrain
to near 110F across the lower deserts by the middle of next week.
Heat headlines will likely be needed for the Grand Canyon as early
as Monday and potentially some of the lower elevations by
Wednesday.

&&

.AVIATION...Friday 04/18Z through Saturday 05/18Z...VFR conditions.
Winds SW 10-15 kts with gusts 20-25 kts before 02Z, then becoming
VRB 5-10 kts.

OUTLOOK...Saturday 05/18Z through Monday 07/18Z...VFR conditions.
ISO afternoon -SHRA/-TSRA possible in vicinity of KJTC/KSOW on
Saturday and then near a KFLG-KJTC line on Sunday. Brief MVFR
conditions and gusty outflow winds possible near TS. Winds S/SW 5-15
kts each afternoon.

&&

.FIRE WEATHER...Saturday and Sunday...Warmer and drier conditions
are expected, with only a slight chance of showers and storms in the
White Mountains on Saturday, expanding to the Mogollon Rim on
Sunday. Winds south through west 5-15 mph with gusts 20-25 mph each
afternoon. Minimum afternoon values RH 10-20%.

Monday through Wednesday...Hot, slight chance of showers and
thunderstorms each afternoon over the higher terrain. West/southwest
winds 10-15 mph each day, along with minimum RH 10-20% .

&&

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

&&

$$

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

For Northern Arizona weather information visit
weather.gov/flagstaff