607
FXUS66 KSGX 162105
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
205 PM PDT Mon Sep 16 2024

.SYNOPSIS...
Gusty southwest to west winds will continue through this evening.
Periods of light showers or drizzle are expected Tuesday morning,
with areas of drizzle west of the mountains Wednesday morning.
For Wednesday evening into Thursday or Friday, unsettled weather
is expected again with additional chances of precipitation. Drier
and warmer conditions expected by the weekend.

&&

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

So far today, we`ve seen isolated light rain and periods of gusty
westerly winds. Rainfall totals and peak wind gusts have been
headlined on our weather.gov/sandiego website. This afternoon is
expected to be mostly dry, with slight chances of isolated light
showers and drizzle early Tuesday, mainly for San Diego County and
the coastal foothills of the mountains. Periods of gusty winds
will continue through this evening. Strongest winds will be
through passes and into the deserts. Peak gusts of 35 to 45 mph
are expected over the mountain ridge tops, desert slopes, and High
Desert. Gusts 45 to 55 mph are expected in the San Diego deserts
with gusts up to 65 mph possible through the Cajon Pass.

Weaker winds and mostly dry conditions are expected after Tuesday
morning. A few degrees of warming are expected Tuesday west of the
mountains and in the low desert with 5 to 10 degrees of warming in
the mountains and High Desert. It looks like the marine layer will
be deep enough on Wednesday morning to allow for areas of drizzle to
develop west of the mountains and along the coastal mountain
slopes.

On Wednesday an upper level low will begin to dig south along the
coast of the Pacific Northwest. Latest guidance has the low moving
slower, now moving inland across Central and Southern California
on Thursday. This system is expected to bring additional chances
of precipitation to Southern California. Some showers or drizzle
may develop late Wednesday night but the highest chances of
precipitation are on Thursday. With the slowing of the trough,
slight chances of showers have been added to the forecast for
Friday morning. This system looks like a warmer one, so only minor
fluctuations in temperatures are expected for Tuesday through
Thursday. Current ensemble guidance does not have a very
significant uptick in winds with ensembles indicating winds may be
weaker than today. NBM chances of wind gusts greater than 45 mph
are 35 to 45 percent for Wednesday and Thursday afternoon and
evenings and confined to wind prone passes, like the San Gorgonio
Pass.

Due to the slow down of the trough, there is more uncertainty in the
high temperature forecast for Friday. Some warming may occur
compared to Thursday, but more substantial warming may not occur
until the weekend. High temperatures will be several degrees
warmer for Saturday with high temperatures for next Sunday warming
to a few degrees above average for the deserts to around 5
degrees above average for the coast and valleys, mostly in the 90s
for the inland valleys and 100 to 105 for the lower deserts.

&&

.AVIATION...
162030Z...Low clouds with bases varying 2000-3500 feet MSL and tops
to 5200 feet will continue to shroud the coast to mountains,
including higher terrain obscured in BR. -RA or -DZ likely anywhere,
but most likely in foothills under these clouds. When/where this
precip occurs, vis could be reduced 2-5SM and cigs drop to 1500 feet
MSL. Low clouds and fog to fill in the entire coastal basin again.

Confused cloud pattern overnight into Tuesday so confidence in the
KSAN TAF BKN-OVC arrival and departure is low. Any morning low
clouds are expected to scatter out Tuesday starting at the coast and
work its way inland, scattering out last far inland valleys.

Smoke from the Line, Bridge and Airport fires will continue to
reduce VIS in mountains, with hazy conditions over the Inland Empire
and parts of the deserts.

West-northwest winds will gust 40-50 knots through mountain passes,
continuing into tonight. Local moderate up/downdrafts in lee (east)
of mountain ridges.

&&

.MARINE...
No hazardous marine conditions are expected through Friday.
Although, northwest gusts around 20 knots are expected in the outer
waters this afternoon and evening and again Wednesday afternoon and
evening.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until 9 PM PDT this evening for Apple and Lucerne
     Valleys.

     Wind Advisory until midnight PDT tonight for San Diego County
     Deserts-San Gorgonio Pass Near Banning.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE...Small