946
FXUS65 KPSR 040510
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1010 PM MST Sat Oct 3 2026

.UPDATE...
Updated Aviation

&&

.KEY MESSAGES...

- Unseasonably strong high pressure will allow temperatures warm
significantly by the middle of next week as lower desert highs reach
up to 10 degrees above normal.

- Periods of breezy to locally windy conditions can be expected
across south-central and southwestern Arizona through Monday with
gusts reaching 20-30 mph.

- Dry weather with zero rain chances will persist into much of next
week.

&&

.SHORT TERM /TODAY THROUGH SUNDAY/...
The upper atmosphere remains mostly unchanged with an area of strong
high pressure remaining dominant over the Desert SW, centered over N
AZ, while low pressure remains to the regions east. The strong high
pressure is expected to peak this weekend with H5 heights reaching
between 590-591 dam, which is near the 97th percent of climatology
for this time of year. With this unseasonably strong high
pressure, temperatures are expected to keep trending 3-5 degrees
above normal throughout the weekend. Afternoon highs across the
western lower deserts and along the Colorado River valley will be
the upper 90s to low 100s. Meanwhile, south-central AZ will be
slightly "cooler" with temperatures mostly staying below the century
mark, however very localized areas may still see those dreaded
triple digits. Overnight lows will also remain well above normal (8F-
12F), flirting with and likely breaking record warm lows throughout
the weekend and into next week. Expect lows across the region to be
in the upper 70s to low 80s, and with the combination of above
normal highs and lows, moderate HeatRisk across the western deserts
has started to develop.

With the aforementioned pattern remaining in place dry northeasterly
winds aloft continue due to the increased pressure gradient. Winds
associated with this pressure gradient will continue to produce
gusts reaching 20-30 mph at times across southcentral and southwest
AZ. Periods of gusts between 35-40 mph could develop Sunday morning
in the higher terrain of E And SE AZ as well as in southwestern AZ
as winds become channeled through terrain features, before quickly
relaxing going into the afternoon hours. For the western portions,
patches of blowing dust will be possible.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Heading into next week, deterministic and ensemble guidance show the
unseasonably strong ridge weaken and retrograde wwd as an upper-lvl
trough progresses through the Intermountain West. This will allow
temperatures to dip a few degrees on Monday afternoon, although
highs will still remain slightly above normal. The aforementioned
trough will provide a temporary weakness in 500 mb hghts over
southcentral AZ early next week, however positive hght anomalies
will still exist over SE CA and SW AZ which will maintain highs in
the low 100s. As ridging aloft begins to expand back over N AZ by
mid-week, significant warming is progged to arrive with highs across
the western deserts topping out around 100-105 degrees and
approaching 100 degrees for the central AZ deserts on Wednesday and
Thursday. These will likely be the hottest days of the forecast
period before another trough potentially arrives onto the west coast
by Friday into next weekend. Overall, subsidence aloft coupled with
N-NE flow in the mid-lvls will maintain a dry forecast with near
zero rain chances each day next week.

&&

.AVIATION...Updated at 0510Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
Gusty east winds will be the main weather concern through Sunday
night under clear skies. Confidence is very good that east winds
will maintain modest speeds overnight, falling just short of LLWS
criteria. Wind speeds will rapidly increase mid/late Sunday morning
with a period of 25-35kt gusts possible before gradually weakening
through the afternoon. Forecast uncertainty grows Sunday evening as
gusts may be maintained longer than is typical before weakening
overnight. Depending on wind gust strength Sunday afternoon and
recent land use, lofted dust affecting slantwise visibility may be
an issue Sunday late afternoon/evening around sunset.


Southeast California/Southwest Arizona including KIPL and KBLH:
No major weather concerns will exist through Sunday night under
clear skies. Confidence is excellent that an E/NE wind component
will be favored, though a light north drift or variable direction
will be possible around sunrise. A few gusts near 20kt may affect
KBLH in the afternoon.

&&

.FIRE WEATHER...
Dry conditions with slightly above normal temperatures are
anticipated through this weekend before further warming occurs into
the middle of next week. MinRHs will mostly range from 15-25% over
the western districts to 25-35% for the eastern districts with fair
to good overnight recovery area-wide. A persistent breezy easterly
gradient wind will continue through at least Monday. Expect winds to
remain elevated around 8-12 mph with early morning and afternoon
gusts up to 20-30 mph.

&&

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

&&

$$

SHORT TERM...Ryan
LONG TERM...Salerno
AVIATION...18
FIRE WEATHER...Salerno