318
FXUS65 KPSR 111720
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1020 AM MST Thu Dec 11 2025

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- Well above normal temperatures will be seen across the region
  through at least the weekend with some locations flirting with
  record highs.

- Dry and tranquil conditions will prevail through at least next
  week.

&&

.SHORT TERM /TODAY THROUGH SUNDAY/...
The weather pattern will continue to support unseasonably warm
temperatures and dry conditions into next week. A strong upper
level ridge is currently centered just off the coast of southern
California with the ridge now extending through the Desert
Southwest. H5 heights have risen to near 585dm across the region,
or into the 97th percentile of climatology for mid December.
Temperatures have been a bit slow to respond to the high heights
aloft due to weak flow and poor mixing, in additional to the fact
we are near minimum daylength. El Centro did manage to reach into
the lower 80s yesterday, while Phoenix only reached into the mid
70s. Temperatures today for the south-central Arizona lower
deserts should get a decent boost with most locations reaching
into the upper 70s, while the upper 70s to lower 80s are forecast
for southeast California and far southwest Arizona. The ridge is
forecast to gradually weaken and shift eastward Friday into
Saturday with the ridge axis moving through Arizona late
Saturday/Sunday morning. Temperatures for Friday and through the
weekend will remain very stable with lower desert highs mostly in
the upper 70s to around 80 degrees with the warmest spots likely
topping out in the lower 80s. It would not be surprising to see a
few daily records being tied or broken during this period. Skies
will remain clear through Friday before we see some increasing
high clouds Saturday into Sunday.

&&

.LONG TERM /MONDAY THROUGH NEXT FRIDAY/...
Very little will change as far as the weather pattern for next
week with any weather systems staying across the northern tier
states. Models do show a very weak shortwave trough moving either
through the ridge or overtopping the ridge early next week, but
H5 are shown to only drop briefly to between 580-582dm. This
little feature may cause daytime highs to dip more into the mid
70s by next Tuesday or Wednesday, but guidance favors a rebuilding
of the ridge again by late next week. This should at least
maintain highs in the mid to possibly upper 70s late next week
with some potential for reaching 80 degrees again by next weekend.
Other than some occasional higher level clouds, the air mass will
stay dry across the region 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 will exist through Friday morning
under clear skies. Winds will favor light, diurnal tendencies with
extended periods of variable or calm conditions.

&&

.FIRE WEATHER...
Warm and dry weather will prevail across the region into next week
with temperatures running 8-13 degrees above normal. Winds are
expected to remain light every day 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%.

&&

.CLIMATE...Daily Record Highs

   Phoenix
   -------
12/11  81 (1977)
12/12  79 (2010)
12/13  82 (2010)
12/14  78 (2010)
12/15  79 (1969)

&&

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

$$

SHORT TERM...Kuhlman
LONG TERM...Kuhlman
AVIATION...Smith
FIRE WEATHER...Kuhlman
CLIMATE...Benedict