499
FXUS65 KPSR 161938
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1238 PM MST Thu Apr 16 2026

.KEY MESSAGES...

- A weather system passing our region to the north will result in
  marginally breeziness conditions this afternoon followed by
  locally windy conditions and elevated fire weather concerns
  Friday for portions of Southeast California.

- A Wind Advisory has been posted from early Friday morning until
  the early afternoon for an area stretching from Joshua Tree NP
  to along the Lower Colorado River Valley.

- After a brief stint of near and below normal temperatures over
  the next few days, readings will rebound with widespread
  afternoon highs in the 90s expected by the end of the weekend.

&&

.SHORT TERM /TODAY THROUGH FRIDAY/...
Current WV imagery and 500mb analysis reveals the Desert Southwest
caught in the middle of two approaching areas of low pressure, each
of which will impact conditions through the end of the work week.
The southern most system, currently located off Baja Coast, will
underhand upper-level moisture over the region, providing some
decent cloud cover overhead. The other, more potent disturbance,
currently spinning over the Northern Rockies, will slide further
southeast through the day today, imparting at least some influence
on the region this afternoon. Although not directly over us, the two
troughs will help to tighten up the regional pressure gradient at
least slightly which will help to generate some marginally breezy
conditions this afternoon. Gusts should range generally between
15-25 mph for the majority of the region, with the higher end of
that range focused over higher terrain areas and the Lower
Colorado River Valley. Locally higher gusts can be expected in the
typically breezier spots of Western Imperial County. Lower desert
highs will be a degree or few warmer than yesterday, with readings
in the middle to upper 80s being common.

Stronger winds can be expected as the northern most storm slides
through the Great Basin and Intermountain West tonight into Friday,
dragging a cold front along with it. This boundary will help
increase our thermal and pressure gradients even further, helping to
push gusts upwards of 35-45 mph, mainly from an area extending from
Joshua Tree NP toward the Lower Colorado River Valley. Locally
higher gusts will be possible around enhanced terrain features and
gap wind prone areas. These strong winds will present difficult
travel conditions, especially for high profile vehicles along
portions of I-10 around and west of Blythe, CA, and some blowing
dust channels cannot be ruled out. Due to the high confidence for
gusts exceeding 40 mph, a Wind Advisory has been posted for the
stretch of area mentioned above, valid from 3 AM through 1 PM
MST/PDT Friday. Other breezy spots will be the Imperial Valley and
portions of wester Yuma and La Paz Counties. However, gusts for
these areas should range closer to 25-35 mph, though an isolated
advisory-level gust would not be surprising.

The passage of the cold front will provide the region with at least
a brief cool down to end the work week. Lower Desert temperatures
will hover near to below normal, with the greatest departure from
typical values this time of year being observed over western
portions of our forecast area. Putting those words into numbers,
Friday`s afternoon highs will range in the lower to middle 80s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Ensembles advertise the overall pattern stagnating somewhat for a
few days late this weekend into early next week, with upper level
ridging building over the West-Central CONUS and another
relatively potent upper low diving southward from the Gulf of
Alaska and settling off the West Coast. The influence of high
pressure over the region will allow temperatures to rebound over
the weekend, with lower desert highs once again reaching the 90s
and in a decidedly above normal category by Sunday. Something that
is becoming more clear in the global model guidance is that a
strong surface high will shift from the Intermountain West to the
Southern Plains by Sunday, allowing another E/SE`rly gradient wind
event to take shape Sunday morning. This will mostly impact
Southeastern AZ, but likely extend into South-Central AZ higher
terrain east/southeast of Phoenix.

Forecast uncertainty increases considerably heading into the middle
of the upcoming workweek, when the upper low off the West Coast is
expected to move inland over the Great Basin or even over the Desert
Southwest. The uncertainty is reflected in the probabilistic NBM
temperatures, as IQRs for the forecast highs/lows increase to 5F
or greater Tuesday onward. Overall, temperatures should retreat
closer to or even slightly below seasonal normals during the
middle of next week. Another uncertainty is whether the forcing
from the incoming upper low will combine with meager moisture
(mostly in the mid levels) to produce light shower activity over
portions of AZ. However, the vast majority of global guidance
shows the area remaining dry, with PoPs below 10%. From
experience, the track of this low is also not promising to produce
anything more than light precip totals favoring upslope areas and
higher terrain.

&&

.AVIATION...Updated at 1745Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and
Southeast California/Southwest Arizona including KIPL and KBLH:

No significant weather issues will exist through the forecast
period under mid to high cigs. Timing of directional wind shifts
should be similar to the past 24 hours, although west winds will
be maintained around the Phoenix metro longer into Thursday night
than usual. Wind speeds from the mid afternoon through early
evening will be stronger than the past several days with
occasional gusts 15-20kt across the region. For KIPL and KBLH
expect winds to pickup this afternoon with a WNW component and
gusts reaching up to 20-25kts. Expect a period of increased
gustiness at KBLH tomorrow morning with velocities reaching up to
20-25 kts sustained and gusts up to 30kts.

&&

.FIRE WEATHER...
Dry and occasional breezy conditions will prevail through the next
week. Temperatures will cool from near normal today to slightly
below normal Friday, then warm above normal over the weekend. A
weather system passing the region to the north will send a cold
front down the Colorado River Valley and produce gusty winds
Friday morning, with gusts to 30-45 mph for portions of Southeast
CA and Southwest AZ. Winds will gradually relax heading into the
afternoon as humidity drops into the single digits. Elevated and
locally critical fire weather conditions are expected to
materialize for portions of the western deserts Friday as a
result, particularly along the Lower Colorado River Valley.
Afternoon MinRHs below 15% and at times in the single digits will
be common through the next 7 days, with minor day to day
variations. Overnight recoveries between 30-50% tonight will drop
into 15-30% range Friday and Saturday nights.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Wind Advisory from 3 AM to 1 PM MST Friday for AZZ530.

CA...Wind Advisory from 3 AM to 1 PM PDT Friday for CAZ560-561-564-
     565-568>570.

&&

$$

SHORT TERM...RW
LONG TERM...Whittock
AVIATION...95
FIRE WEATHER...Whittock

NWS Phoenix (PSR) Office