935
FXUS65 KPSR 140537
AFDPSR
Area Forecast Discussion
National Weather Service Phoenix AZ
1037 PM MST Mon Apr 13 2026
.UPDATE...Updated 06Z Aviation Discussion.
&&
.KEY MESSAGES...
- A weather system will swing through the region today and tonight
bringing more breezy to locally windy conditions as well as
chances for light showers focused over the Arizona high terrain.
- Weak high pressure will settle back into the region during the
middle of the week leading to drier and slightly warmer
conditions.
&&
.SHORT TERM /TODAY THROUGH TUESDAY/...
Large scale troughing continues over much of Western CONUS with
upper level moisture being advected into the region from the SW.
Following close behind the main troughing feature is another smaller
disturbance that has already begun to merge with the main trough
and is diving down California`s coast, moving closer to the
Desert SW. However, a patch of dry air can be seen on GOES water
vapor imagery to the regions west, which will dry out the upper
levels as it pushes inland along with the aforementioned trough
starting this evening and overnight. Hi-Res CAMs suggest some
isolated showers likely to develop however will be fighting
against a dry boundary layer, so much of the lower deserts will at
most see a trace while the Arizona higher terrain may receive a
few hundredths to up to a tenth of an inch in localized areas. As
the disturbance continues to weaken and lifts to the northeast on
Tuesday, a few light showers may still be possible during the
morning hours over far eastern Arizona.
Otherwise, breezy to windy conditions will continue across the vast
majority of the region this afternoon as these systems move through.
Wind gusts this afternoon/evening will be between 20-30 mph, with
periods of 30-40 mph possible in southeastern California. Winds
across most of the region are expected to relax by midnight tonight,
with the exception of southeast California, where winds will persist
through the morning hours. Thanks to these systems, afternoon high
temperatures will be below normal for this time of year. Today`s
high temperature will be in the mid to upper 70s across southeast
California, and in the upper 70s to low 80s in the Phoenix area.
By tomorrow, southeast California will begin to warm back up into
the upper 70s to low 80s as the system pushes farther eastwards,
while the Phoenix area will be in the upper 70s. This will be the
coolest day of the week for the Phoenix area.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Shortwave ridging will briefly move through the region on
Wednesday leading to another quiet day while temperatures warm
back into the mid 80s for most lower desert locations. A robust
Pacific low pressure system will also move through the Pacific
Northwest on Wednesday on its way to the Great Basin by Thursday.
Ensembles continue to favor a more northern track with this low
across the Great Basin and into the Central Rockies while also
weakening. The base of the trough may clip Arizona, but all
indications so far keep any system energy and moisture well to our
north. However, the fairly close proximity of the system should be
enough to bring more breezy to locally windy conditions on
Thursday and/or Friday while also leading to a slight dip in
temperatures likely for Friday.
Looking ahead for next weekend a more significant ridge is
expected to move over the Western U.S. with the NBM suggesting a
return of highs back into the 90s by Sunday. Fortunately, this
warm up may be fairly brief as guidance mostly favors another
trough moving in from the west northwest at some point during the
first half of next week.
&&
.AVIATION...Updated at 0535Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
A cold front moved through the area earlier this evening bringing
breezy conditions and VCSH to all four terminals. Some residual
breeziness (gusts into the upper teens to around 20 kt) remain at
all terminals except KIWA, but should subside over the next 1-2
hours. A few areas of VCSH/virga also remain in the Phoenix Metro,
but should also exit the area over the next 1-2 hours. After wind
speeds subside tonight, winds should generally be around 10 kt or
less through the rest of the TAF period, with some occasional
gusts into the teens possible tomorrow afternoon. Confidence
remains low in a E/SE wind shift overnight/early tomorrow morning
and winds may just stay W/SW or go light and variable. If winds
were to go SE this looks to occur during the 12-17Z window.
Westerly winds will reestablish tomorrow afternoon, with winds
returning to their diurnal tendencies, with an E/SE shift
expected late tomorrow night. Cloud cover (with bases around 7-9
kft) will gradually clear out overnight with mostly clear skies
returning tomorrow morning.
Southeast California/Southwest Arizona including KIPL and KBLH:
Wind speeds will be aob 10 kt through the TAF period at both
terminals. Winds will predominately have a westerly component at
KIPL. At KBLH, current southwesterly winds will go northerly late
tomorrow morning before going southeasterly tomorrow night. Skies
will remain mostly clear.
&&
.FIRE WEATHER...
A weather system will pass through the region this evening through
the overnight period, with chances for mostly high terrain
showers, but CWR will be less than 10%. Today will again be quite
breezy with afternoon and evening wind gusts between 20-30 mph
over much of the area. MinRHs today will rise to 25-30% before
lowering to 15-25% Tuesday and 10-15% starting Wednesday as dry
air fully encompasses the region. Overall light winds are forecast
for Tuesday and Wednesday while temperatures warm back into the
normal range by Wednesday. Dry conditions will prevail through the
rest of the week, but a passing weather system on Thursday and
Friday should bring another round of breezy to windy conditions.
The low humidities and the increased winds late week may bring a
period of elevated fire weather conditions heading into the
weekend.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
SHORT TERM...Ryan
LONG TERM...Kuhlman
AVIATION...Berislavich
FIRE WEATHER...Kuhlman/Ryan
NWS Phoenix Office
Tucson, AZ 
