677
FXUS65 KPSR 142320
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
420 PM MST Tue Oct 14 2025

.UPDATE...Updated Aviation Discussion

&&

.KEY MESSAGES...

-Dry and tranquil weather conditions will prevail during the
 remainder of the week with temperatures remaining below normal.

-Breezy to locally windy conditions can be expected this
 afternoon and evening, with the strongest winds confined over
 southeast California.

&&

.SHORT TERM /Today through Wednesday/...
After a very active weather stretch that started late last week,
a much quieter weather pattern is finally taking shape across the
region. Early afternoon water vapor satellite shows a potent upper
trough centered near the central CA coastline with dry
southwesterly flow entrenched across the region. This dry air
advection has scoured out most of the moisture that has been in
place since late last week with the latest SPC mesoanalysis
showing PWAT values now ranging between 0.5-0.6". As a result,
mostly clear skies are being observed with rain chances now near
zero and likely to remain this way for the foreseeable future.
With the upper trough in the process of moving onshore, height
falls and a tightening of the regional pressure gradient will
continue to promote breezy to locally windy conditions this
afternoon and evening, with the strongest winds expected across
portions of SE CA, particularly across the higher terrain areas.
Heading into Wednesday, as the upper trough moves inland through
the Great Basin and the pressure gradient weakens, winds will
gradually relax.

Under the influence of the upper trough, afternoon high temperatures
will remain a solid 8-13 degrees below normal during the next couple
of days. High temperatures this afternoon will top out in the low
80s across the lower deserts. Even lower afternoon highs are
expected on Wednesday with readings only topping out in the mid to
upper 70s. Early morning lows will also be below normal with
readings bottoming out in the mid to upper 50s across the more rural
areas to around 60 degrees across the more urban areas.

&&

.LONG TERM /Thursday through Monday/...
The core of negative height anomalies will have lifted into the
northern Rockies/plains and weakened substantially during the latter
half of the week, albeit with positively tilted troughing lingering
into the SW Conus. Persistent westerly flow will ensure further
moisture erosion throughout the week while H5 heights hovering below
578dm will keep temperatures sequestered 4F-8F below normal, though
larger than expected ensemble numerical spread only yields moderate
confidence with temperature potentially warming faster than
forecast. Nevertheless by the weekend, there is good model agreement
that some form of shortwave ridging will build into the SW Conus
with H5 heights possibly exceeding 588dm and temperature rebounding
into a near normal range. The majority of ensemble output shows the
next Pacific trough early next week remaining north of the forecast
area before potentially amplifying downstream over the plains (a
very La Nina-like pattern). However, enough membership (including
the operational GFS) shows vorticity and strong jet energy digging
close enough to the CWA to possibly incur strong, gusty winds and
reemergence of below normal temperatures. Regardless, there is
little to no model evidence of any better moisture source returning,
and the prevailing dry weather should continue.

&&

.AVIATION...Updated at 2320Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation concerns are expected during the TAF period.
Breezy conditions will gradually relax through the remainder of
the evening with light winds prevailing overnight. The usual
nightly E`shift does not appear certain as W winds appeared to be
favored with window of variability during this timeframe. FEW-SCT
low clouds with bases 4-6k ft will be present through much of the
nighttime hours. Greater cloud coverage may be observed to the
east of the Phoenix airspace

Southeast California/Southwest Arizona including KIPL and KBLH:
Besides some marginal breeziness this evening at both terminals
with gusts 20-25 kts, no major aviation concerns are expected over
the next 24 hours. Winds will favor a W`rly component through the
period with some variability being observed overnight at KBLH.
FEW- SCT low clouds with bases around 7-8k ft will be present
through tonight before clear skies take over by Wednesday morning.


&&

.FIRE WEATHER...
Drier air across western districts will completely sweep through the
entire region today and Wednesday bringing the start to a prolonged
period of more tranquil weather. While minimum humidity levels will
only fall into a 30-50% range the next couple days, values will
retreat closer to a 20-35% range during the latter half of the week.
Overnight recovery will largely be good to excellent above 50%.
Locally gusty winds 20-30 mph will be common today, particularly
across western districts, however winds will be far weaker the
remainder of the week with limited gustiness.

&&

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

$$

SHORT TERM...Lojero
LONG TERM...18
AVIATION...RW
FIRE WEATHER...18