632
FXUS65 KPSR 240938
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
238 AM MST Mon Nov 24 2025

.KEY MESSAGES...

- Patchy dense fog will develop across portions of the lower
  deserts early this morning and will burn off by mid-morning.

- Dry and tranquil weather conditions are expected through the
  workweek with temperatures gradually warming to slightly above
  normal by the end of the week.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...
Upper level water vapor satellite imagery early this morning
shows broad troughing stretching from the Desert SW into the
Plains. Objective analysis and upper level water vapor satellite
imagery show the closed low associated with the trough (and that
brought rain to the region this past weekend) is now centered over
eastern CO/western KS. With the desert SW on the back side of the
trough there is an abundance of subsidence which has resulted in
clear skies across the region. The lower levels are still holding
onto moisture though which is evident in the current dew point
temperatures, which range from the upper 40s to mid 50s across the
lower deserts. Low temperatures this morning are forecasted to be
very similar to the dew point temperatures which is an excellent
setup, in conjunction with very light to calm winds, for the
development of fog this morning. Looking at the nighttime
microphysics satellite product areas of dense fog can already be
seen in the valleys of the higher terrain areas north of the
Phoenix Metro. Lighter fog can also be seen starting to develop
across portions of SE CA and SW AZ. Fog will likely develop in low
lying areas and river valleys. Models continue to show the
potential for this fog to become dense, with visibilities falling
below 1 mile at times. Drivers should exercise caution when
encountering lower visibilities during the morning commute. Any
fog that develops will burn off by 9-11am.

With broad troughing still influencing the region today, there will
be one more day of below normal temperatures with afternoon high
temperatures around 2-4 degrees below normal. Highs this afternoon
are forecasted to be upper 60s to low 70s across the lower deserts
and in the low to mid 60s across the higher terrain. Tomorrow
temperatures will return to near normal. This is due to rising 500
mb heights, which is in response to high pressure building over the
eastern Pacific. Afternoon high temperatures tomorrow will be in the
the low to mid 70s across the lower deserts and in the mid 60s to
low 70s across the higher terrain areas. In addition to warming
temperatures the rising heights aloft will also promote dry and
tranquil weather conditions across the region.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Models continue to be in good agreement that dry and tranquil
weather conditions will continue across the region through at least
the end of the workweek. Heights aloft will continue to rise as the
aforementioned high pressure system continues to build and
eventually moves and over our region during the middle of the week.
Temperatures will peak during the middle of the week, when the
high pressure is overhead. During this timeframe afternoon high
temperatures will be 3-6 degrees above normal, with forecasted
highs in the mid to upper 70s across the lower deserts and in the
upper 60s to low 70s across the higher terrain. On Friday, a dry
shortwave trough, out ahead of the next weather system, looks to
move through the region cooling us off a couple degrees (but still
near to slightly above normal). Morning low temperatures during
the latter half of the workweek will be in the 40s across much of
the CWA but more urban areas will see lows in the low to mid 50s.


By this weekend, global ensemble members all show a deep trough
traversing the region by some point either during the weekend or
early next week, but they differ on the exact timing. They are in
good agreement that the trough will be moving down into our region
from the Pacific NW (inland trajectory) and not move down along the
eastern Pacific Ocean and then move inland like the last low
pressure system did. With this trough taking an inland trajectory
the system won`t be bringing a lot of moisture to the region. PWATs
currently look to only rise to a 0.5-0.7" range (the ECMWF and
Canadian Ensemble have PWATs in a 0.5-0.7" range, but the GEFS has
PWATs staying below 0.6"). This increase in moisture (in
combination with forcing from the trough and terrain itself)
would likely support showers across the higher elevations to the
north and east of the Phoenix Metro. Showers across the lower
deserts will likely be harder to come by with this amount of
moisture and would need more help than that of the higher terrain
areas. Nevertheless, another weather system will be moving through
the region either late this weekend or early next week and would
support showers across at least portions of the CWA along with
cooling temperatures. With this weather system temperatures look
to cool back off below normal. Stay tuned for future updates.

&&

.AVIATION...Updated at 0505Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
The main aviation concern during the TAF period will reduced VIS
due to morning BR/FG. KIWA remains the most likely terminal to
observed these conditions, but there still is a fair amount of
uncertainty regarding coverage. Therefore, a TEMPO group remains
in the TAF to reflect this lower confidence. As mentioned in the
previous discussion, KPHX may see some reduced VIS as well but
there too much uncertainty exists to include any prevailing or
TEMPO groups in the TAF at this time. However, some VCFG or even
some BCFG cannot be ruled out. KSDL, and KDVT appear unlikely to
see any operational impacts. Winds during the period will resume
their diurnal trends after some extended periods of VRB to calm
conditions during much of the overnight.

Southeast California/Southwest Arizona including KIPL and KBLH:
The main aviation concerns during the next 24 hours will be
potential FG development, especially at KIPL. VIS near or even
less than 1SM seem likely for the terminal between 12-15Z, but BR
may begin to cause operational impacts as early as 10Z. FG should
quickly dissipate after 15Z. At BLH, confidence regarding reduced
VIS is not as high but a TEMPO group for 5SM as been left in to
reflect at least some potential to see impacts. Winds during the
period will be light with extended periods of VRB to calm
conditions.

&&

.FIRE WEATHER...
One more day of below normal temperatures is expected today
before rising back to near to slightly above normal by the middle
of this week. Dry and tranquil weather conditions return to the
region today and will continue through the workweek. MinRHs will
range from 40-60% with excellent overnight recovery of 80-100%
for today. Drier air will filter into the region by the middle of
the week with MinRHs bottoming out around 25-35% by Wednesday and
Thursday. Even with the drier air overnight recoveries will still
be in a 60-80% range. Despite a few upslope gusts in the teens to
lower 20 mph range, winds will remain light and follow normal
diurnal patterns.

&&

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

$$

SHORT TERM...Berislavich
LONG TERM...Berislavich
AVIATION...RW
FIRE WEATHER...Berislavich