886
FXUS65 KPSR 291923
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1223 PM MST Mon Sep 29 2025

.KEY MESSAGES...

- A dry and quiet weather pattern will prevail throughout the
  week with near zero rain chances.

- Temperatures will gradually warm from near normal to slightly
  above normal by the latter half of this week as a ridge of high
  pressure builds over the region.

- A dry weather system passing north of the region will bring
  breezy conditions and slightly cooler temperatures this
  weekend.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...
The latest water vapor satellite imagery as well as streamline
analysis depict a weak upper-level ridge across the region. A much
drier air mass has settled into the region with mostly clear skies
being observed. Temperatures this afternoon will continue to be
slightly below normal with highs in the lower 90s across the lower
deserts.

For Tuesday, a broad trough will be situated over the
Pacific Northwest with quasi-zonal flow in place across the Desert
Southwest. Weather conditions will continue to remain dry and
tranquil. Temperatures will continue to warm a couple of more
degrees to more seasonable levels with highs reaching the mid 90s
across the lower deserts.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
From mid to late week, ensemble and deterministic models are in
agreement that a high amplitude ridge will build over the Desert
Southwest while a cutoff low develops over California. 500 mb
hghts will gradually increase to around 588-590 dam by the end of
the week resulting in highs across the lower deserts increasing
from the mid 90s on Wednesday to the upper 90s to around 100
degrees by Thursday and Friday. Global models continue to indicate
the aforementioned shortwave trough eventually diving across the
Great Basin this weekend which will result in a slight cool down
and breezier conditions across southcentral AZ. Given the trajectory
of this system remaining north of the forecast area and the lack
of any adequate moisture return, dry conditions with near zero
precipitation chances are expected to persist.

&&

.AVIATION...Updated at 1710Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No aviation concerns are expected through Tuesday morning. Winds
will favor light and diurnal trends with periods of variability,
especially during directional shifts. Other than a FEW afternoon
CU aoa 8k ft and some high cirrus moving in tonight, skies will be
mostly clear.

Southeast California/Southwest Arizona including KIPL and KBLH:
No aviation concerns are expected over the next 24 hours. Winds
will favor light and diurnal trends, with extended periods of VRB
to calm conditions. Other than a FEW afternoon CU and some high
cirrus moving in this evening, skies will be mostly clear.

&&

.FIRE WEATHER...
Temperatures will gradually warm above normal through the middle of
this week as a ridge of high pressure builds over the forecast area.
Expect much drier conditions to materialize each day with MinRHs
ranging from 25-35% this afternoon and falling to around 15-25%
through the end of this week. Overnight recovery will range from
fair to good tonight and generally remain in the fair category
through this week. Winds will follow light and diurnal tendencies
for the next several days with some modest afternoon upslope gusts.

&&

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

$$

SHORT TERM...Lojero
LONG TERM...Salerno
AVIATION...RW
FIRE WEATHER...Salerno