297
FXUS65 KPSR 081119
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
419 AM MST Mon Dec 8 2025

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- A weak and dry weather system will move through the region today
  and induce some breezy conditions, with afternoon wind gusts up
  to 15 to 25 miles per hour.

- Dry and quiescent weather conditions will continue through at
  least the next 7 days.

- Temperatures will steadily climb through the upcoming workweek,
  with highs likely reaching 8 to 13 degrees above daily normals.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...
A subtle, positively-tilted, shortwave trough will slide through
AZ today and induce some breezy winds across the region. Strongest
wind gusts will be along the Lower Colorado River, peaking around
20-25 mph. The only other evidence of the passing shortwave today
will be some passing high clouds, mainly across the northern half
of AZ. This short wave is not expected to cool temperatures. In
contrast temperatures are actually forecast to warm a few degrees
from yesterday, with lower desert highs today expected to reach
the middle 70s in most locations. The warming will be a result of
the large Pacific high to the west nudging eastward slightly, and
of course because the shortwave will be too weak to have any
influence on the lower level thermal profile.

There will be some lingering breeziness around the region
Tuesday, but the weak shortwave will be out of the area by late
morning and the pressure gradient will gradually weaken. This
will also allow temperatures to warm another degree or two, under
clear skies.

&&

.LONG TERM /WEDNESDAY THROUGH THIS WEEKEND/...
A gradual warming trend will continue through late week as global
ensembles remain in excellent agreement in maintaining anomalous
high pressure over the central and southern Pacific coast, with
dry northerly to northwesterly mid-level flow across the Desert
Southwest. Ensembles show 850mb temperature anomalies peak
Thursday and Friday, at around the 95th to 97th percentile. This
will result in temperatures up to 10-13 degrees above normal, with
lower desert high temperatures forecast around 80 degrees to end
the week and start the weekend. Latest forecast highs from the NBM
are also within a couple degrees of daily records, including in
Phoenix Thursday through Sunday. It is not tremendously uncommon
to reach 80 degrees this time of year, as most daily records are
around 80-85 degrees in December and January. It is actually
somewhat common for lower desert communities to reach 80 degrees
a few times each Dec-Jan, and it has become more common during the
last 10-20 years.

Heading through this weekend global ensembles show the large scale
pattern across the Southwest becoming flatter, with more westerly
flow, for at least a few days. This reduction in 500mb height
anomalies will result in slightly cooler temperatures heading into
the beginning of next week, but still above normal by up to 8-10
degrees. Overall, the long term outlook does not support a lick of
rain. The desert is gonna desert.

EXTENDED LOOK: Looking out at longer range models there is still
no sign of any significant weather pattern change. Ensembles
maintain positive height anomalies through week 2, which means a
continuation of above normal temperatures. The NBM shows very
little spread in the temperature forecast (4 degrees max) through
December 18th, indicating a high confidence forecast. There is
also no sign of rain still. Global ensemble 90th percentiles do
not show any measurable precipitation until closer to December
20th.

&&

.AVIATION...Updated at 1120Z.

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

No significant aviation weather concerns expected through the TAF
period under mostly clear skies. Winds will mostly follow typical
diurnal trends at all terminals, with speeds at or below 6 kts at
all but KBLH. At KBLH, northerly winds this afternoon up to 10
kts and gusts to around 15 kts are expected. Extended periods of
VRB are also expected at all terminals, and winds may briefly
shift lightly out of the SW Tuesday morning at KPHX, but with
speeds of 4 kts or less.

&&

.FIRE WEATHER...
Warm and dry weather will prevail across the region through this
week. Temperatures will be above normal and gradually warm to 8-13
degrees above normal by the end of the week. A brief bout of gusty
winds, up to 15-25 mph, can be expected across the Lower Colorado
River Valley and AZ high terrain midday today through this
evening. There will also be some lingering gusts Tuesday morning
through early afternoon. Otherwise, winds will remain light and
follow diurnal tendencies. Humidities over the next week will stay
above critical levels with afternoon MinRHs mostly ranging
between 20-30%, followed by good overnight recoveries to around
50-70%.

&&

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

$$

SHORT TERM...Benedict
LONG TERM...Benedict
AVIATION...Benedict
FIRE WEATHER...Benedict