899
FXUS66 KSGX 231040
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
340 AM PDT Mon Sep 23 2024

.SYNOPSIS...
Today will be dry and warmer with high temperatures for inland
areas around 4 to 8 degrees above average. Not much change on
Tuesday, then gradually cooler for Wednesday and Thursday. Friday
may be slightly warmer followed by slow cooling for next weekend
with increasing spread in the high temperature guidance due to the
uncertain placement of a weak low pressure system in the vicinity
of southern California. Night and morning coastal low clouds will
spread into portions of the western valleys late each night.

&&

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

.SHORT TERM (Today through Wednesday)...
Low pressure will weaken across the area with high temperatures
today around 5 degrees warmer than Sunday, near average near the
coast to 4 to 8 degrees above average inland, mostly into the 90s
for the inland valleys and 102 to 108 for the lower deserts.

The marine layer has become a little shallower with areas of
reduced visibility in fog across the Orange County coastal plain
and for inland coastal areas into the western valleys in San
Diego County.

Not much change is expected for Tuesday, then a weak low pressure
system off the California coast may bring a few degrees of
cooling for Wednesday and Thursday.

&&

.LONG TERM (Thursday through Sunday)...
That weak low pressure system may move farther off the California
coast on Friday with high temperatures slightly warmer. For next
weekend, that weak low pressure system may move back towards
southern California with differences in model placement and
timing. The deterministic NBM has slight cooling for Saturday and
Sunday, but with increasing spread in the high temperature
guidance.


&&

.AVIATION...
230930Z...Coast and western valleys...Low clouds based at 600-900
feet MSL with tops to 1600 feet. Vis reduced 0-5SM on higher
coastal terrain and westernmost valleys. Scatter out 16-18Z, but
with only partial or intermittent clearing at immediate coast. Low
clouds with similar bases/tops/vis redeveloping along the coast
01-04Z, moving inland to a similar extent overnight into Tuesday.

Inland Valleys/Mountains/Deserts...Mostly clear today and tonight.

&&

.MARINE...No hazardous marine conditions are expected through
Friday.

&&

.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...17
AVIATION/MARINE...MM