984
FXUS65 KPSR 130829
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
129 AM MST Fri Nov 13 2026

.KEY MESSAGES...

- An incoming weather system will begin to cool temperatures and
  increase rain chances today and Saturday.

- Sunday and Monday will be warm and dry before a series of
  weather disturbances will bring occasional rain chances and
  cooling temperatures back to the Desert Southwest by Tuesday.

&&

.SHORT TERM /TODAY THROUGH SATURDAY/...
The short wave trough that will bring cooler and wetter weather to
the Desert SW starting today is currently in the Eastern Pacific
just off the southern CA coastline. This system will move quickly,
passing through southern AZ and Northern Mexico over the course of
today. PWATs will increase to near 200% of normal, which, in
conjunction with the energy from the short wave troughing feature
rain chances will also increase, with PoPs peaking (30-60%) this
afternoon across south-central AZ, then into the eastern higher
terrain heading into the evening hours. Most of the expected shower
activity will remain relatively light, talking about a few hundredths
to at most a tenth of an inch, a few isolated thunderstorms
resulting in briefly heavier rainfall rates cannot be ruled out
given that there will be a least a few hundredths J/KG of CAPE
present.

Behind the short wave just discussed is another short wave that will
quickly move in from the northwest. However this next system will
remain across northern AZ. This will lead to rain chances being
mostly confined to the north with the lower deserts forecasted to be
dry, while the higher terrain areas could squeeze out an additional
0.05"-0.10" Saturday.

Outside of rain chances, these systems will also being in cooler
temperatures as H5 heights will drop between 564-567 dam on Friday
and 570-573 dam on Saturday. Afternoon highs will be in the upper
70s for Friday then as the first short wave passes temperatures will
cool into the low 70s across south-central AZ while out west
temperatures will remain in the mid to upper 70s. after the first
system passes low temperatures will lag in response, resulting in
morning lows in the mid to upper 50s starting Saturday morning.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Sunday will be a down day for shower activity with a brief period
of shortwave ridging and some slight dry air advection from the
northwest. This will lead to considerably less clouds, virtually
no rain chances and temperatures climbing back into the upper 70s
by Monday. Models remain in good agreement that another northern
Pacific waves will continue to be ejected southeastward toward the
U.S. West Coast starting early next week. Currently models
suggest the next potential system reaching the California coast
early Monday before reaching our region Monday night into Tuesday,
where additional rain chances will return to the forecast with
NBM PoPs peaking between 50-80% in south-central AZ and the higher
terrain areas, however this far out this may need to be adjusted
based of how the track of this low progresses. By Wednesday models
are pointing towards yet again another low system, however larger
discrepancies between models are evident for this system. Due to
this confidence is low for rain chances by mid to late next week
as things are too inconsistent at this time.

Despite if these next systems bring rain to the region or not, a
more significant cooling trend can be counted on by the middle of
the week as these series of weather systems move in from the
northwest. They will likely usher in a cooler air mass with
afternoon highs trending more towards the upper 60s to low 70s,
the higher or lower end of this range largely being dependent on
the depth and position of the systems.

&&

.AVIATION...Updated at 0520Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
A period of VCSH/SHRA with gusty erratic winds and CIGs as low as
6-8K ft AGL is anticipated Friday afternoon, mainly between
20-02Z. An isolated storm or two may also develop, but chances are
too low (10%) for inclusion in the 06Z TAF package. Light easterly
winds are favored through Friday morning. There is moderate
confidence winds will veer SSW-SSE by Friday afternoon before
turning back E-SE by the evening. SCT to BKN mid and high clouds
will be common through most of the TAF period. Lower clouds, with
bases around 4-6K ft AGL, are expected Friday night into Saturday
morning and additional low-topped showers are likely to develop
Saturday morning, but mostly stay north and east of the terminals.

Southeast California/Southwest Arizona including KIPL and KBLH:
Winds at KIPL will favor a W`rly component through most of the TAF
period. KBLH will see VRB through much of tonight and Friday
morning before an increase in S`rly winds develops. Wind speeds at
both terminals will remain light through Friday morning and then
increase heading into the afternoon and evening with occasional
gusts up to 20 kts at KBLH and 20-25 kts at KIPL. An increase in
clouds Friday morning in expected, with lowest bases down to
around 7K ft AGL. Cloud coverage decreases again through the
afternoon and evening.

&&

.FIRE WEATHER...
A more unsettled weather pattern will begin to develop starting
today and is expected to persist well into next week as a series
of weather disturbances moving through the region will bring
occasional rain chances and cooler temperatures. Minimum humidity
values will increase today to between 30-40%. These higher minimum
humidity are expected to remain elevated through much of next
week. Expect overall light winds today before increasing Friday
through early Saturday, mainly across the western districts, with
peak gusts mostly staying under 25-30 mph.

&&

.HYDROLOGY...

Gila: A Flood Warning remains in effect from Painted Rock Dam
through the Dateland area through at least early next week due to
water released from the dam. Water release levels have now risen
to 3000 cfs and are expected to remain at this release level
through the next several days. This will have the potential to
flood farm fields and low-water crossings along the river
downstream from the dam.

&&

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

$$

SHORT TERM...Ryan
LONG TERM...Ryan
AVIATION...Benedict
FIREWEATHER...Lojero/Ryan
HYDROLOGY...Lojero