418
FXUS65 KPSR 080520
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1020 PM MST Fri Nov 7 2025

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- Above normal temperatures with dry conditions will prevail
  through at least the middle of next week.

- High temperatures across the lower deserts will peak Sunday and
  Monday with some local daily records possible.

&&

.SHORT TERM /Today through Sunday/...
Early afternoon objective analysis indicates dampened ridging with
weak NW flow across the SW Conus as low amplitude shortwaves and
strong northern stream jet energy remains sequestered over the Great
Basin/central Rockies. However, models remain in excellent agreement
depicting downstream North Atlantic blocking forcing a rapid pattern
amplification over the Conus this weekend as a deep Hudson Bay
vortex dislodges into the Great Lakes/Upper Midwest and pronounced
ridging expands and intensifies over the western Conus. Locally,
forecast confidence is excellent that this pattern evolution of
strong subsidence and H5 heights quickly rising near or above 588dm
will result in temperatures steadily warming to much above normal
levels. In fact, readings 5F-10F above normal Sunday may flirt with
some daily records with NBM output suggesting better than a 75%
chance of KPHX breaching its daily record.

&&

.LONG TERM /Monday through Friday/...
The aforementioned high amplitude ridge will gradually weaken
through the first half of next week as a trough of low pressure sets
up well west of the California coast. As this occurs, heights aloft
will decrease slightly over the Desert Southwest which will result
in a lower desert highs falling from the upper 80s on Monday into
the mid 80s Tuesday and Wednesday. The only sensible change to the
weather through midweek will be increasing high clouds starting on
Tuesday.

Eventually by late next week, the trough over the eastern Pacific
will begin to deepen and bring a plume of Pacific moisture onto the
West Coast resulting in better chances for widespread measurable
precipitation across California. Latest global models and ensemble
members project the trough will eventually move onshore sometime
next weekend in which our region will also see a slight increase in
rain chances, however the timing and magnitude of this system is
still very uncertain and thus forecast confidence is still quite low
at this time. This uncertainty is also reflected in the NBM
interquartile temperature spread next weekend which is around 15
degrees for both highs and lows.

&&

.AVIATION...Updated at 0520Z.

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

No weather concerns will exist through Saturday night under clear
skies. Trends in wind speeds and directional shifts will be
nearly identical to the past 24 hours. Prolonged periods of nearly
calm conditions will be common.

&&

.FIRE WEATHER...
Warm and dry conditions with above normal temperatures will prevail
through this weekend and into much of next week. Afternoon minimum
humidity will bottom out between 15-20% over the several days with
overnight recoveries up to 40-60%. Winds will remain light,
generally 15 mph or less with occasional afternoon gusts and will
tend to follow a typical diurnal upslope/nocturnal drainage pattern.

&&

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

$$

SHORT TERM...18
LONG TERM...Salerno
AVIATION...18/Benedict
FIRE WEATHER...Salerno