895
FXUS66 KSGX 250407
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
907 PM PDT Fri May 24 2024

.SYNOPSIS...
Cooling will continue through Saturday with gusty southwest to
west winds in the mountains and deserts. The strongest gusts occur
this afternoon and evening with the stronger gusts to 40 to 50
mph, locally 60 to 65 mph below the San Gorgonio Pass. Night and
morning coastal low clouds will extend inland across all of the
valleys and onto the lower coastal slopes of the mountains with
slower daytime clearing for coastal areas. High pressure to the
south will bring warming for Sunday through Thursday. The marine
layer will become shallower with night and morning coastal low
clouds only extending into western portions of the valleys by the
middle of next week.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

.Evening Update...
Gusty winds continue for areas of the San Gorgonio Pass and the
Coachella Valley this evening. Peak gusts have been over 50 MPH in
the pass with a peak wind gust of 39 MPH at Palm Springs
International Airport. Windy conditions will continue in this area
through the night into much of Saturday. Cloud cover continues to
slowly fill into portions of the eastern LA metro area this
evening. The deep marine layer in place will once again provide a
chance for drizzle for places near the coast and in adjacent
valleys. Forecast change this evening included blending in some
of the latest HREF model guidance to our cloud forecast on
Saturday. There is high confidence in mostly cloudy conditions for
much of the day tomorrow in western San Diego county, but
confidence becomes lower for the Inland Empire and even lower for
Orange County.

High pressure will build into the region by Monday into next
week with warmer weather. This will bring a shallower marine
layer, so the sunniest day overall this holiday weekend will be
Memorial Day itself. Have a fun and safe weekend, everyone!

.Previous Discussion (144 PM PDT Friday)...

Short-term guidance suggests some slow clearing over the Inland
Empire this afternoon, but most areas closer to the coast will
likely see intermittent clearing, at best. This trend is expected to
continue into Saturday with persistent onshore flow in place. There
is a slight chance that the onshore flow leads to a reverse clearing
event at the coast tomorrow, but confidence in this occurring is
rather low at this time. Future soundings will help to assess the
inversion strength and depth and lend more confidence to the degree
of clearing tomorrow. The marine layer looks to deepen to around
4500 feet tonight, which will likely support patchy drizzle into
tomorrow morning. The onshore flow is expected to be strongest
today, with winds gusting 40 to 50 mph across much of the mountains
and deserts this afternoon and evening. Higher gusts look to occur
through and just below the San Gorgonio Pass, where gusts of 60 to
65 mph are expected.

Sunday kicks off a warming trend for SoCal as upper level ridging
builds in overhead. Highs will climb several degrees both on Sunday
and Monday, followed by slower and more gradual warming through
midweek. Most areas will still remain slightly cooler than normal
through midweek, but the lower deserts will top out a few degrees
warmer than seasonal normal starting Monday. This translates to
highs of 99 to 105 degrees each day Monday through Thursday, with
Wednesday and Thursday being the warmest days in the lower deserts.
For most other locations, Wednesday and Thursday will be when
temperatures rebound back to seasonal normals. The marine layer will
also steadily decrease in depth during this time, though there will
still be some degree of marine layer clouds each morning over the
coasts and valleys.

&&

.AVIATION...
250400Z...Coast/Valleys/Foothills...Widespread stratus with bases
1600-3000 ft MSL and variable tops 2500-5500 ft MSL will continue
through 19Z Sat, with bases rising to 2100-3500 ft MSL Sat afternoon
with continued tops to 5500 ft MSL, continuing after 00Z Sun. Local
VIS 3-5 SM will occur in DZ mainly 09Z-18Z Sat. Higher terrain will
be obscured at times.

Mountains/Deserts...Mostly clear skies will prevail through Sat
evening, except for areas of terrain obscurations below 5500 ft MSL
on the coastal slopes at times. Areas of surface wind gusts of 25-45
knots from the west will occur from the mountain crests east through
the desert slopes and into the deserts, including near San Gorgonio
Pass, will continue through Sat evening, strongest through 15Z Sat
and again after 00Z Sun. Local VIS 3-5 SM will occur in local BLDU.

&&

.MARINE...
West to northwest winds around 20 knots will occur in the outer
coastal waters (30-60 NM from the coast) each afternoon and evening
through Monday.


&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until 2 AM PDT Saturday for San Gorgonio Pass Near
     Banning.

PZ...None.

&&

$$

PUBLIC...APR
AVIATION/MARINE...Maxwell