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000
FXUS65 KPSR 090959
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
259 AM MST Tue Apr 9 2024

.SYNOPSIS...
High pressure will build over the region over the next couple days
leading to a rapid warming trend and temperatures easily rising
into an above normal category starting Wednesday. The warmest days
this week are likely to be Thursday and Friday with lower desert
high temperatures topping out in the lower nineties. A dry weather
system is then likely to stall out just to the west of the region
later this week leading to breezy to locally windy conditions on
Friday and Saturday. This system should eventually move through
our region at some point early next week dropping temperatures to
around or slightly below normal.

&&

.DISCUSSION...
The dry disturbance that moved through the region yesterday is now
nearly completely into Mexico with a strong upper level ridge
already moving in from the west. Today will be a bit of a
transition day in between weather systems, but significant warming
aloft will already begin to mix down by this afternoon as
temperatures warm into the low to mid 80s, or right around
seasonal normals. As the ridge moves right overhead Wednesday into
Thursday, the strong warming trend will continue with some
western lower desert locations seeing their first 90 degree day of
the year on Wednesday. NBM forecast highs then show the bulk of
the lower deserts topping out in the lower 90s on Thursday and
Friday with a few spots likely reaching 95 degrees. This will mark
our first taste of 90 degree weather this year, but it will fall
at least five degrees shy of any daily records.

On Thursday, models are still advertising a weak cut-off low
forming well west of Baja, but it is expected to quickly get
absorbed into a larger scale trough that is expected to develop
off the California coast. Guidance still shows the remnants of
this shortwave moving through our region on Friday, but it will
pass through unnoticed. A much stronger wave is forecast to dive
southward off the coast of California becoming a quasi-stationary
closed low that stays just to our west through at least Saturday,
likely even Sunday. The initial impact with this system is
expected to be the increase in winds across our region on Friday
and Saturday, with temperatures starting to cool starting
Saturday. There is still some model spread with the eventual track
of the low as it moves through the Southwestern U.S., but as of
now the majority of the members favor the low clipping the
northwestern portion of the Desert Southwest around next Monday.
Available moisture should also be very lackluster, so as of now
there are no chances for rain in our forecast. Due to this passing
trough and models favoring a continuation of a troughing pattern
over the Western U.S. through the middle of next week,
temperatures for at least the first half of next week should be
closer to seasonal normals.

&&

.AVIATION...Updated at 0530Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation weather concerns will exist through the TAF
period under mostly clear skies. Expect nearly typical diurnal
wind patterns. Northwesterly directions will be favored over the
next several hours at KPHX and KIWA. Confidence is moderate that
NW winds will eventually give way to periods of variability, or
potentially switch E around sunrise at KPHX. By late morning to
early afternoon, winds will pick up out of the W-NW across all
terminals, with sustained speeds mostly aob 10 kt and gusts into
the mid-to-upper teens.

Southeast California/Southwest Arizona including KIPL and KBLH:
Gusty north winds will be the main aviation weather concern over
the next 24 hours, particularly at BLH, under clear skies. Winds
overnight will favor NW, followed by NNW to N winds increasing
after sunrise. During the afternoon, gusts will gradually subside
and directions will return to a more W`rly component into the
early evening.

&&

.FIRE WEATHER...
Dry conditions and warming temperatures will prevail over the
next few days as strong high pressure builds over the region. For
today, the western districts will see breezy afternoon winds with
gusts between 20-25 mph and MinRHs dipping into the upper single
digits, while the eastern districts will see gusts between 15-20
mph. Winds Wednesday will be relatively light, while MinRHs reach
to around 10%. High temperatures will warm into the mid 80s today
and to the upper 80s to around 90 degrees Wednesday. High pressure
is likely to continue to influence the region late week into the
coming weekend as high temperatures peak mainly in the lower 90s
Thursday and Friday. A weather system setting up off the coast of
California later this week will also promote breezy to locally
windy conditions Friday and Saturday, while humidities remain low.
This could lead to elevated fire weather conditions where there
are any dry fine fuels.

&&

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

$$

DISCUSSION...Kuhlman
AVIATION...Whittock
FIRE WEATHER...Kuhlman