Tustin Marine Corps Air Stat, California Weather Forecast Discussion

599
FXUS66 KSGX 020935
AFDSGX
Area Forecast Discussion
National Weather Service San Diego CA
235 AM PDT Thu Oct 2 2025
.SYNOPSIS...
Today will be a few degrees warmer with cooling for Friday into
Saturday as a low pressure system moves inland into California and
Nevada. There will be stronger southwest to west winds for the
mountains and deserts on Friday with gusts to 35 to 45 mph along
the east slopes of the mountains. The marine layer will deepen for
Friday into early Saturday with coastal low clouds spreading into
portions of the inland valleys for Friday night. Low pressure
from the north will spread cooling of a few to around 5 degrees
inland for Sunday and Monday. Then a few degrees warmer for
Tuesday and another 5 degrees warmer for Wednesday.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
.SHORT TERM (Today through Saturday)...
High pressure to the east will bring a few more degrees of warming
today. This will be followed by cooling for Friday into Saturday
as a low pressure system moves inland into California and Nevada.
On Friday, there will be stronger onshore flow on Friday with
stronger southwest to west winds for the mountains and deserts
with gusts to 35 to 45 mph along the east slopes of the mountains.
The marine layer is around 1200 to 1400 feet deep with a weak
inversion. Satellite imagery shows only patchy coverage of coastal
low clouds. Patchy night and morning low clouds will increase in
coverage and spread farther inland for Friday into early Saturday
as the marine layer deepens. The low clouds for late Friday night
into early Saturday will spread into portions of the inland
valleys and possibly onto the lower coastal mountain slopes.
&&
.LONG TERM (Sunday through Wednesday)...
Low pressure from the north will spread cooling of a few to around
5 degrees inland for Sunday and Monday with high temperatures on
Monday 5 to 10 degrees below average for inland areas. High
temperatures on Monday will range from around 70 near the coast to
the mid 70s to around 80 for the Inland Empire with the lower
deserts around 90.
This will be followed by warming for Tuesday and Wednesday with
Wednesday high temperatures still a few degrees below average,
ranging from around 70 near the coast to the lower to mid 80s for
the Inland Empire with the lower 90s for the lower deserts.
&&
.AVIATION...
020930Z....Coasts/Valleys...Variable low clouds based 1000-1500 feet
MSL will gradually increase through 14Z. Local vis reduced 1-5SM on
higher coastal terrain. Scatter out expected by 16Z. Low clouds
develop after 03Z coastal areas and after 08Z inland tonight into
Friday. Bases should be around 1500 feet MSL, rising over 2000 feet
MSL early Friday, filling much of the coastal basin.
Mountains/Deserts...Mostly clear and VFR conditions today and
tonight.
&&
.MARINE...
Northwest winds Friday afternoon and evening over the outer waters
near San Clemente Island could lead to hazardous conditions for
small craft. Otherwise, no hazardous marine conditions are expected
through Monday.
&&
.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

NWS SGX Office Area Forecast Discussion