Area Forecast Discussion
Issued by NWS Phoenix, AZ

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682
FXUS65 KPSR 022354
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
454 PM MST Thu Oct 2 2025

.UPDATE...Updated Aviation Discussion.

&&

.KEY MESSAGES...

- After a gradual trend upwards, temperatures peak this afternoon
  with a few spots reaching into the triple digits

- Low pressure will brush the Desert Southwest Friday through the
  front of the weekend bringing breezy to locally windy
  conditions and cooling temperatures

- A warming trend will commence once again heading into the front
  half of next week.


&&

.SHORT TERM /TODAY THROUGH THURSDAY/...
WV imagery reveals a dry airmass entrenched across the Desert
Southwest has high pressure continues to encompass the region.
Meanwhile, the Pacific Northwest continues to be under the influence
of a Pacific Low just off shore that has been providing them with
cool and wet conditions. More on that system in just a minute.
With the aforementioned persist high still overhead, regional
temperatures across our forecast area will continue their upward
trend that we have seen over the past few days with perhaps a few
locations reaching the triple digits this afternoon. Today will
likely be the peak of the warming trend so we can rest easy
knowing that the start of this October will not be anywhere close
in terms of heat to what was experienced last year at this time.
It isn`t uncommon to see triple digits in October (though last
year may make one think otherwise) as the average last day of 100
degree readings at Sky Harbor is October 5th.

Friday looks to be a bit of a transition day for the region as the
previously mentioned Pacific Low begins its decent toward the Great
Basin. With decreasing heights aloft, temperatures will be a few
degrees cooler compared to today (especially for locations out in SW
AZ and SE CA) with readings in the lower to middle 90s. Further east
across the lower deserts of south-central AZ, the influence of the
ridge will hold on for just a little longer so afternoon highs will
be slightly above normal, with perhaps a few spots reaching the
triple digits once again. The main impact with the closed-low will
be the development of breezy to locally windy conditions across the
region Friday afternoon and evening. Most locations can expect gusts
20-30 mph. Further west however, higher gusts of 30-40 mph are
likely with advisory level gusts (40+ mph) favored over portions
of southwestern Imperial County. With high confidence of winds
reaching that threshold, a Wind Advisory has been posted for that
area.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
The base of the trough will move through N AZ Saturday morning
dragging with it a Pacific cold front. Winds will still gust 20-30
mph across SE CA and the Lower CO River Valley behind the front
Saturday morning. Additionally, this will lead to gusts of 20-25 mph
across the higher terrain in E AZ Saturday afternoon and evening.
This cold front will lead to a fairly substantial cool down. With
temperatures forecasted to be 5-10 degrees cooler on Saturday than
Friday. Lower desert high temperatures are forecasted to be in the
upper 80s to low 90s, with higher terrain areas seeing highs in the
low-to-mid 80s.

This trough will quickly move into the Plains by Sunday with another
trough digging over the Intermountain West Region leaving broad
troughing over our area to end the weekend and start next week. The
first trough will bring in much drier air and the second trough will
keep the drier air in place. Heights aloft will slowly rise as the
secondary trough pushes eastward through the middle of next week,
which will lead to a gradual warming trend. Afternoon high
temperatures are forecasted to warm from the upper 80s to low 90s
(mid 80s) on Sunday to the mid to upper 90s (upper 80s) by Wednesday
across the lower deserts (higher terrain). With drier air in place,
morning low temperatures will feel more fall-like and are forecasted
to be in the 60s (mid 50s to low 60s) through the beginning of next
week across the lower deserts (higher terrain). But with the rising
heights aloft, morning low temperatures will also slowly warm just
like the high temperatures. With morning lows forecasted to be
back near the 70 degree mark by Wednesday across portions of the
lower deserts, mainly for the more urban areas. Ensembles are in
good agreement that dry conditions will continue through at least
the middle of next week.

&&

.AVIATION...Updated at 2354Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No aviation weather concerns under mostly clear skies are
anticipated through the forecast period. Winds will continue to
follow typical diurnal tendencies with speeds remaining aob 7 kts.
Winds out of the W are expected to take hold at KPHX early this
evening before switching back around to the E tonight. Expect
periods of light and variable to calm conditions throughout the
TAF period. Gustier winds will develop Friday afternoon out of the
W/SW.

Southeast California/Southwest Arizona including KIPL and KBLH:
No aviation weather concerns under clear skies are expected over
the next 24 hours. Winds at KIPL will predominantly favor the W
with some gusts to around 20 kts this evening. At KBLH, winds will
favor the W-SW. Gustier winds will develop Friday afternoon.

&&

.FIRE WEATHER...
Temperatures will be above normal today and tomorrow across the
central and eastern districts as a ridge of high pressure
strengthens over the forecast area. Temperatures will remain near
normal across the western districts. Dry conditions will persist
through the first half of next week with MinRHs bottoming out
each afternoon around 15-30%. Overnight moisture recovery will
generally remain in the fair category around 40-60%. A dry cold
front will move through on Saturday, which will allow for
overnight recoveries to fall to the 30-50% range. Winds will
follow light and diurnal tendencies today, however a weather
system passing north of the region will result in an uptick in
breezy conditions across the region on Friday. Expect gusts to
increase to around 20-25 mph region-wide with locally higher gusts
upwards of 30-40 mph both Friday and Saturday. Highest winds are
expected across SE CA and the higher terrain in E AZ. The passage
of this weather system will also result in the arrival of cooler
temperatures.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory from midnight tonight to 5 AM PDT Saturday for
     CAZ562.

     Wind Advisory from 3 PM Friday to midnight PDT Friday night for
     CAZ566.

&&

$$

SHORT TERM...RW
LONG TERM...Berislavich
AVIATION...Smith/Benedict
FIRE WEATHER...Berislavich