269
FXUS65 KPSR 261706
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1006 AM MST Wed Nov 26 2025

.UPDATE...Updated 18Z Aviation Discussion.

&&

.KEY MESSAGES...

- Dry and tranquil weather conditions are expected through the
  remainder of the week with slightly above normal temperatures.

- A weather system arriving late Sunday and Monday is expected to
  bring much cooler temperatures and chances for precipitation
  focused more over the Arizona high terrain.

&&

.SHORT TERM /TODAY THROUGH FRIDAY/...
Upper level ridging has fully moved into the Southwestern U.S.
with H5 heights rising to around 585dm later today, or into the
90th percentile of climatology. The higher heights today along
with clear skies and drying conditions will help to push daytime
highs well into the 70s across the lower deserts. By Thursday into
Friday, the ridge will gradually weaken and shift to the east,
but temperatures will stay above normal with highs staying in the
mid 70s across the lower deserts. At the same time, a weakening
upper level trough well to our southwest will briefly bring in
some higher level clouds on Thursday before skies clear once again
on Friday. Overnight lows will also rise slightly under the ridge,
but the drier boundary layer conditions will generally keep lows
from the mid to upper 40s across rural desert areas to 50-55
degrees for urban locations.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
The first part of this weekend will stay quiet across the region,
but we will transition into a broad troughing pattern with a fast
moving disturbance first passing across northern Utah into
Colorado. The lowering heights will help to bring temperatures
down to fairly close to normal readings on Saturday, but
conditions will stay dry and skies will remain mostly clear. As we
enter a more active weather pattern once again, guidance has been
trying to bring a disturbance through our region at some point
Sunday into early next week.

Ensembles had initially been quite favorable for a slower and
more impactful weather system, but over the past couple of days
have gradually shifted toward a progressive system with a more
northerly track. There are still some ensemble members (maybe 15%)
calling for a slower system with more precipitation, but if the
trends continue it probably will not amount much precipitation.
The latest NBM only gives 10-15% PoPs for the western deserts,
20-30% for Phoenix, and 30-40% for the Arizona higher terrain.
The current timing as of now brings the system through here late
Sunday and early Monday with highs dropping from around normal on
Sunday to a few degrees below normal for next Monday-Wednesday.

The active weather pattern should continue into the latter half of
next week with guidance currently indicating a larger Pacific
weather system dropping southward along the West Coast,
potentially stalling out briefly to our west around next Wednesday
and Thursday. If this occurs, it could result in a decent
precipitation event at some point late next week for the Desert
Southwest.

&&

.AVIATION...Updated at 1710Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:

No aviation concerns this forecast period. Winds will remain light
and overall from a northeast to east direction in the Phoenix
valley. At the SE California terminals, N/NW directions will be
preferred. There will be a few high clouds, with a general
increase in clouds late in the TAF period midday Thursday.

&&

.FIRE WEATHER...
Dry and tranquil weather conditions will continue into the weekend
with temperatures rising to around 3 to 6 degrees above average
lasting through Friday. Expect MinRHs between 25-35% through
Friday and 35-45% over the weekend with overnight recoveries
remaining good. Winds will be less than 10 mph and follow their
normal diurnal tendencies with only marginal upslope gusts into
the upper teens to low 20s. A fast moving weather system should
then move through the region late Sunday and Monday providing
mostly high terrain precipitation chances.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&

$$

SHORT TERM...Kuhlman
LONG TERM...Kuhlman
AVIATION...Frieders
FIRE WEATHER...Kuhlman