904
FXUS65 KPSR 241047
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
347 AM MST Fri May 24 2024

.SYNOPSIS...
A weak disturbance will pass over the region this weekend leading to
breezy to locally windy conditions and cooler Saturday high
temperatures. The strongest winds are expected this evening over
portions of Southeastern California, and widespread breeziness can
be expected on Saturday. By Memorial Day, highs will have heated
back up to around the century mark and remain near to slightly above
normal through the work week.

&&

.DISCUSSION...
Current mid level wv imagery and streamline analysis shows a
positively tilted shortwave trough moving onshore along the Pacific
Coast. Ahead of this feature, mostly zonal flow remains over the
Desert Southwest this morning. Heights will not begin to fall until
late today, so high temperatures this afternoon will reach similar
values to those observed yesterday in the mid to upper 90s across
the lower deserts. As the shortwave trough traverses the Great Basin
on Saturday, highs will be notably cooler at between 5-10 degrees
below normal for this time of year in the upper 80s to low 90s.

Widespread breezy to locally windy conditions will accompany the
aforementioned shortwave as it traverses the Great Basin this
weekend. This evening, winds will pick up primarily over portions of
Southeastern California such as JTNP and Southwestern Imperial
County including the Imperial Valley. Gusts are expected to peak
between 35-45 mph in these areas, with gusts up to 55 mph in the far
Southwestern corner of Imperial County along high terrain. Wind
Advisories have been issued for portions of Imperial County for late
this afternoon through this evening. Confidence in winds reaching
Advisory criteria in JTNP and locations further east in Imperial
County is low at this time, though HREF mean gusts are upwards of 35
mph in some of these areas this evening. Elsewhere across the lower
deserts, gusts will peak in the 20-30 mph range today. On Saturday,
afternoon breeziness will be widespread and South-Central AZ high
terrain will see peak gusts around 30 mph as the trough axis passes
overhead and quickly ejects east northeastward.

In the wake of the shortwave disturbance, heights will begin to rise
on Sunday and a ridging pattern will set up over the western CONUS
by Memorial Day. Global ensembles are in good agreement that this
ridging pattern will persist through much of next week, with some
slight discrepancies in strength/position of the ridge apparent in
the WPC cluster analysis. Temperatures into the middle 90s can be
expected by Sunday, rising further into the upper 90s to around 100
degrees for some areas by Monday. Day-to-day temperatures will
continue to increase through the middle of next week as the ridge
continues to dominate our forecast area. Afternoon highs by Tuesday
across the lower deserts are forecasted to range between 100-105
degrees, with similar conditions expected again on Wednesday. This
pattern will also promote tranquil and very dry conditions, with no
rain chances anticipated potentially through the end of May.

&&

.AVIATION...Updated at 0536Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:

No major aviation weather concerns are expected through the TAF
period. Winds will continue to favor diurnal tendencies, with a
period of southerly winds expected mid/late morning Friday before
veering toward a westerly component during the early afternoon.
Breezy conditions will return once again Friday afternoon as
gusts climb to around 20 kts. Otherwise, FEW-SCT high clouds will
pass over the region throughout the period.

Southeast California/Southwest Arizona including KIPL and KBLH:

West winds will continue through most of the TAF period at KIPL
while winds remain southerly at KBLH. Wind gusts at the terminals
will climb to around 25-30 kts going into tomorrow afternoon
before further increasing to around 35 kts at KIPL at times by
late afternoon into the evening. Strong winds may generate areas
of blowing dust, which could lead to some slantwise and surface
visibility reductions. Otherwise, FEW-SCT passing high clouds will
move over the region throughout the period.

&&

.FIRE WEATHER...
Elevated fire weather conditions will exist today and Saturday over
parts of the western districts and high terrain of the eastern
districts as a weak system helps to generate breezy to locally windy
conditions. Strongest winds (35-45 mph peak gusts) will be focused
over the western districts and enhanced terrain areas, with 20-30
mph gusts expected elsewhere. MinRH values during this timeframe
will increase slightly from 10-15% today, to 10-20% Saturday.
Overnight recoveries will be fair tonight and Saturday night at
around 30-50% and locally higher in high terrain locations. Hot and
dry conditions will persist beyond Saturday, with generally lighter
winds speeds and typical afternoon breeziness each day. Daily highs
will reach the century mark in many lower desert locations by Monday
and values generally top out between 100-105 through the middle
of next week.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...Wind Advisory from 4 PM this afternoon to 9 AM PDT Saturday for
     CAZ562.

     Wind Advisory from 4 PM this afternoon to 11 PM PDT this evening
     for CAZ563-566-567.

&&

$$

DISCUSSION...Whittock
AVIATION...Smith
FIRE WEATHER...Whittock/RW