384
FXUS66 KSGX 090403
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
903 PM PDT Tue Oct 8 2024

.SYNOPSIS...
Incrementally cooler each day through the weekend. Daytime
temperatures 5 to 15 degrees above averages for inland areas until
additional cooling by Sunday and Monday. Marine layer will
persist along the immediate coast and dry conditions elsewhere.

&&

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

Today was another hot day inland and three climate sites tied or
set records today. See the Preliminary Record Event Report for
details. Overall, today`s high temps were 10 to 15 degrees above
seasonal averages for the inland areas and deserts. The marine
layer is marginally deeper than yesterday and low clouds are
increasing in coverage while spreading locally up to 10 miles
inland. Persistence may be the best forecast and low clouds and
fog will likely follow a similar pattern of clearing to recent
days.

A weak upper level trough will move inland over SoCal and
dissipate by Wednesday afternoon, allowing the upper ridge to
reassert itself over the region for Thursday and Friday. This
will have negligible impacts on conditions so that inland
temperatures remain well above seasonal averages while a shallow
marine layer under a strong inversion moderates temperatures in
the coastal areas.

For next weekend...Another trough moves in from the northwest,
lowering temperatures a little more so that by next Monday daytime
temperatures could be near seasonal averages for inland areas. The
marine layer could deepen and spread its influence farther inland. There
is still significant spread in model solutions so beyond Thursday,
the forecast details remain quite uncertain.

&&

.AVIATION...
090300Z...Coast...Low clouds rebuilding and moving inland again this
evening and will move inland up to 10-15 miles overnight. CIGs of
100-500 ft MSL and VIS 0-3 miles will prevail throughout coastal
areas and into western valleys. Periods of VIS below 1 SM at times
is likely at coastal airports (including KSAN/KCRQ/KSNA), most
likely 09-12Z. Clouds clearing to the immediate coast 15-17Z Wed,
with low clouds/fog breaking up along beaches towards 20-22Z. Low
clouds with similar bases likely moving back inland 02-05Z Thu.

Valleys/Mountains/Deserts...Mostly clear skies with unrestricted VIS
will continue through Wed.

&&

.MARINE...Areas of dense fog with visibility 1 nm or less will
continue at times through late Wednesday morning. Conditions improve
Wednesday afternoon. Otherwise, no hazardous marine conditions are
expected through Sunday.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.

&&

$$

PUBLIC...PG
AVIATION/MARINE...CSP