504
FXUS65 KPSR 012001
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
101 PM MST Sat Nov 1 2025

.KEY MESSAGES...

- Dry and tranquil conditions will continue through next week with
  temperatures remaining above normal.

&&

.SHORT TERM /TODAY THROUGH SUNDAY/...
Broad upper level ridging remains in place over the Southwest US,
with an atmospheric river along the northwestern periphery of the
ridge continuing to stream into portions of Washington and
Northern Oregon early this afternoon. Meanwhile, the shortwave
disturbance which moved south and brushed the CA Coast yesterday
has become a weak cutoff low, undercutting the ridge and
centering itself well offshore the Northern Baja Coast. The
resultant upper level pattern just west of our region resembles a
rex block (but only in appearance), with a NNW-SSE oriented
deformation zone apparent in midlevel wv imagery on the western
flank of the cutoff low. Ensembles continue to advertise the axis
of the ridge shifting eastward over the weekend, passing directly
overhead early Sunday and well east of the forecast area Sunday
night. The weak cutoff low is likely to progress much more slowly
and meander towards the SoCal Coast, eventually opening up and
getting absorbed in the northern stream Sunday night. As the
ridge axis passes overhead, ensemble mean H5 heights will peak
near 590 dam. Despite the bump in heights, temperatures may only
increase another 1-2 degrees into Sunday. Expect daytime highs
this weekend to range from the upper 80s over the majority of the
lower deserts to around 90-92F in some of the warmest spots.
Skies will remain clear through at least Sunday afternoon before
high clouds associated with the aforementioned weak cutoff low
move in Sunday night.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
The weather pattern will remain stagnant for our region through
next week and likely longer. The ridge is expected to flatten out
some by the middle part of next week, but overall H5 heights are
still expected to mostly range between 583-587dm through the
period. This will keep temperatures above normal with highs mostly
within a 86-89 degree range across the lower deserts through at
least Wednesday. Other than some mostly thin higher level clouds
on Monday, skies will be clear to mostly clear through the
entirety of next week. Guidance is still suggesting a slight cool
down later next week with highs potentially falling back into the
low to mid 80s, but confidence in the cool down is still somewhat
low given forecast H5 heights may only drop to between 582-585dm.
Either way, the pattern will continue to support dry westerly flow
through all of next week.

&&

.AVIATION...Updated at 1720Z.

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

No aviation weather concerns are expected through the TAF period
under clear skies. Winds will continue to follow normal diurnal
tendencies with extended periods of calm and VRB conditions.

&&

.FIRE WEATHER...
Temperatures will fluctuate a few degrees over the next 7 days, but
remain around 3-8 degrees above normal for early November.
Afternoon minRHs will range between 10-20% areawide through the
upcoming work week. Overnight recoveries will improve slightly
from 20-40% this weekend to 30-50% Monday night onward, with
values on the higher end of that range favoring the western
deserts and especially low-lying areas such as the Lower Colorado
River Valley and Imperial Valley. A few dry weather systems
passing north of the region may temporarily elevate winds but are
not expected to present fire weather concerns. Otherwise, winds
will be light and generally follow diurnal tendencies with minimal
afternoon gustiness.

&&

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

$$

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