Trabuco Canyon, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

336
FXUS66 KSGX 140356
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
856 PM PDT Tue May 13 2025

.SYNOPSIS...
Gusty west winds in the mountains and deserts weakening tonight.
Warmer Wednesday and Thursday with high temperatures a few degrees
below normal. Over the weekend, additional cooling with gusty
winds and a 10-30% chance of precipitation, highest in San Diego
County.

&&

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

Evening update...
Areas of low clouds are quickly redeveloping across much of San
Diego County in the Inland Empire with some thin high clouds
elsewhere. Low clouds should fill in across the coastal basin
overnight. Based on the 00Z KNKX sounding, the cloud deck is too
thin to generate any drizzle, and high-res guidance shows no
precipitation tonight or Wednesday morning. Gusty west winds
continue across the mountains and deserts where gust are currently
around 30-40 mph, with isolated gusts of 50-55 mph in the passes.
Winds will weaken overnight. The Wind Advisory remains in effect
through 5 AM.

Previous discussion...
The main trough axis will be to our east by Wednesday but the region
will maintain an overall troughing pattern with a ridge of high
pressure building over the Eastern Pacific ocean. The overall
troughing pattern will keep high temperatures just below the
seasonal normal through Friday and maintain night and morning low
cloud coverage for the coast and western valleys. A persistent
onshore pressure gradient will maintain elevated afternoon sea
breezes on the desert mountain slopes and deserts. For the
weekend, there is better agreement that troughing will continue to
prevail over the Western United States maintaining cooler,
cloudier, and windier weather. For Sunday there is more agreement
in a deeper trough developing, but there is uncertainty in how
far west or east the trough will be which will impact
precipitation chances. NBM chances of rainfall totals exceeding
0.10" Saturday night through Sunday are 10 to 20 percent, with the
highest chances on the coastal mountain slopes. There is higher
confidence that the eventual depth of the trough will at least
support increased winds and cloud coverage this weekend. NBM
chances of wind gusts exceeding 50 mph for Saturday and Sunday is
60 to 80 percent for wind prone locations in the mountains and
deserts.

By Monday, there is good ensemble agreement that the trough will be
off to our east with upper level ridging beginning to inch closer to
the West Coast. By Tuesday, the majority of ensemble clusters show
ridging over the West Coast. Current forecast follows the NBM with
warming temperatures for Monday and Tuesday.


&&

.AVIATION...
140340Z...Coast/Valleys...SCT-BKN low clouds based near 3000-4000 ft
MSL through this evening. BKN-OVC low clouds will start to fill in
again after about 06Z, though intermittent SCT is possible
overnight, and bases lower to 2500-3000 ft MSL. Good scatter out 14-
17Z with mostly clear skies through Wednesday evening. Low clouds
rebuild from south to north after 06Z Thu, with lower bases around
2000 ft MSL.

.Mountains/Deserts...Mostly clear through Wednesday. Westerly winds
with gusts 25-40 kts will become more localized to the passes and
desert slopes this evening, with MOD UDDFS in lee of mountains, then
calm Wed morning. Confidence moderate on VCTY KPSP seeing wind gusts
over 35 kts through 09Z tonight.

&&

.MARINE...
Stiff west-northwest winds will continue through this evening in the
outer waters. Gusts to 25 kt will lead to hazardous conditions for
small craft, strongest winds near San Clemente Island. A Small Craft
Advisory remains in effect through late tonight. No additional
hazardous marine conditions are expected Wednesday through
Saturday.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until 5 AM PDT Wednesday for Apple and Lucerne
     Valleys-Riverside County Mountains-San Bernardino County
     Mountains-San Diego County Deserts-San Diego County
     Mountains-San Gorgonio Pass near Banning.

PZ...Small Craft Advisory until 11 PM PDT this evening for Waters
     from San Mateo Point to the Mexican Border Extending 10 to
     60 nm out including San Clemente Island.


&&

$$

PUBLIC...SS/CO
AVIATION/MARINE...CSP