909
FXUS65 KPSR 101046
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
346 AM MST Mon Nov 10 2025

.KEY MESSAGES...

- Unseasonably warm weather will persist through the middle of this
  week with near record high temperatures possible again today.

- A fast moving storm system is expected to arrive on Friday,
  bringing gusty winds, lower desert rain, and mountain snow.

- Temperatures are expected to cool well below normal this weekend
  with lower desert highs in the 60s and 70s and lows in the 40s
  and 50s.

&&

.SHORT TERM /Today through Thursday/...
Latest mid-lvl wv imagery and 500 mb streamline analysis reveals
a highly amplified wave pattern across the lower 48. This pattern
has created an immense temperature difference between areas east
of the Rockies where freezing conditions are present and the
Desert Southwest where record setting highs have been observed.
The anomalously strong upper-lvl ridge is now centered over the
Great Basin region and will begin to weaken over the next few
days. Although the ridge will not be as strong today, heights
aloft are still expected to reach 588-589 dam over the western
half of the forecast area which will result in highs topping out
around 90 degrees or near record levels in locations such as Yuma
and El Centro. Farther east in southcentral AZ, highs are expected
to reach the mid to upper 80s which is 8-10 degrees above normal.

As mentioned previously, the ridge will gradually weaken as we head
into the middle of this week with H5 heights falling into a 584-586
dam range over southcentral AZ by Wednesday. This will result in
lower desert highs cooling from the upper 80s to the mid 80s which
is still above normal for this time of year. The only noticeable
change in weather conditions through the middle of this week will
be increasing high cirrus streaming into the forecast area which
will become thicker and more extensive by Wednesday and Thursday.
This influx of upper-lvl moisture will be associated with an
approaching trough of low pressure which is progged to reach the
CA coast by Thursday. Due to the increasing mid-lvl height
gradient associated with this trough moving onshore, we will see
increased breeziness Thursday afternoon and evening across SE
California and SW Arizona.

&&

.LONG TERM /Friday through Monday/...
Deterministic models and ensemble members have come into better
agreement regarding a storm system which will take aim on the
Desert Southwest on Friday. Most EPS and GEFS members show the
Pacific trough deepening over the Great Basin region early Friday
with several members developing a cutoff low before reaching
western AZ on Friday afternoon. Although there are subtle
differences in magnitude and timing within the suite of ensembles,
there is decent agreement that the system will progress through
the region on Friday and depart to the east by Saturday. Moisture
associated with this system still looks to be adequate with PWAT
values rising to around 150-200% of normal. There will also likely
be a strong sfc front that will sweep through the forecast area
from W to E which will provide a focus for lift and help foster
the development of showers and possible a few thunderstorms. NBM
PoPs continue to trend upward and are now 30-60% across southcentral
AZ from Friday morning through Friday night. In addition to the
increasing rain chances, another potential impact from this system
will be gusty winds. Latest model guidance indicates widespread
gusts reaching 25-35 mph with even higher gusts up to 40 mph
across SE California and SW Arizona Friday afternoon. These
stronger gusts could result in localized channels of blowing dust.

As the trough axis passes through the forecast area, we will see a
much cooler airmass being ushered in behind this system. In response,
high temperatures are expected to fall from the mid 80s on Thursday
to upper 60s to low 70s on Friday. Well below normal temperatures
will carry into the weekend making it feel much more fall-like.
Overnight lows will also tumble into the upper 40s to low 50s with
some locations across the high terrain areas NE of Phoenix
bottoming out in the upper 30s on Sunday morning. Cooler than
normal conditions will likely persist into early next week as long
range models indicate another shortwave trough arriving into the
Intermountain West on Monday.

&&

.AVIATION...Updated at 0530Z.

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

Confidence is excellent that winds will retain an easterly
component across the PHX metro throughout the period with some
localized gusts upwards of 15-20 kts possible Monday mid-late
morning, then relaxing over the afternoon. This could present a
minor crosswind concern at KSDL, mainly between 16-19Z. Winds over
SE California will maintain a light NNE to NW fetch with extended
periods of variability to nearly calm conditions. Skies will
remain clear through the early evening on Monday, then anticipate
FEW-SCT cirrus decks to move in Monday night.

&&

.FIRE WEATHER...
Warm and dry conditions with above normal temperatures will
persist through Thursday before a weather system brings cooler
temperatures and chances for wetting rains to the area on Friday.
Afternoon minRHs will mainly range between 15-20% each afternoon
through Thursday before improving to 25-30% on Friday and through
the weekend. Overnight recoveries will range from poor to fair
over the next several nights, with much better moisture recovery
up to 60-80% Thursday night into Friday. Winds will be light,
generally less than 15 mph and follow typical diurnal patterns
through most of this week, however breezy to locally windy
conditions are expected to develop across the western districts
Thursday and Friday.

&&

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

$$

SHORT TERM...Salerno
LONG TERM...Salerno
AVIATION...Whittock/18
FIRE WEATHER...Salerno