Trabuco Canyon, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

854
FXUS66 KSGX 160959
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
259 AM PDT Wed Jul 16 2025

.SYNOPSIS...
A weak low pressure system from the south will bring an increase
in mostly mid level monsoonal moisture on Thursday and Friday
with a chance for mainly afternoon showers and thunderstorms,
mainly for the mountains. The chances are greatest for the San
Bernardino Mountains. Then drier for the weekend into the middle
of next week. Thursday will be cooler for the deserts, but with an
overall slight warming trend for most areas through Wednesday of
next week with high temperatures warming a few degrees. Night and
morning coastal low clouds will continue to 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 Friday)...
A weak low pressure system from the south will bring an increase
in mid level monsoonal moisture on Thursday and Friday with ECMWF
ensemble output showing the peak in precipitable water values late
Thursday afternoon. This will bring a chance for mainly afternoon
showers and thunderstorms on Thursday and Friday, mainly for the
mountains.

The greatest chances are over the San Bernardino Mountains. NBM
chances for measurable rainfall for Big Bear have increased to
around 40 percent on Thursday and 35 percent on Friday. However,
chances for one-quarter inch or more of rainfall have remained
around 10 percent each day with chances for one-half inch or more
of rainfall less than 5 percent.

The marine layer will remain around 2000 feet deep with night and
morning coastal low clouds spreading into the western valleys
late each night. There will be slight day to day changes in high
temperatures through Friday with the deserts a few degrees cooler
on Thursday.

&&

.LONG TERM (Saturday through Tuesday)...
There will be a drying trend for the weekend into early next week
with an overall slight warming trend in high temperatures of a few
degrees from today through Wednesday of next week. Not much change
with the marine layer with night and morning coastal low clouds
spreading into portions of the western valleys late each night.

High temperatures for Wednesday of next week will range from
around average for the deserts to as much as 5 to 10 degrees below
average for portions of the valleys. High temperatures for
Wednesday of next week will range from the lower 70s near the
coast to the mid 80s to mid 90s for the Inland Empire with 106 to
110 for the lower deserts.

&&

.AVIATION...
160915Z....Coast/Valleys...Low clouds based 1400-1800 ft MSL will
continue to move inland to 25-30 miles from shore, with a 75% chance
KONT sees CIGs between 11-16z and KSBD having a 30% chance during
this time frame. Clouds scatter 15-17Z inland and 17-19Z for coastal
areas, with areas of clouds remaining along parts of the immediate
coast all day, particularly in San Diego County. Clouds with similar
bases reform and push back inland after 17/00Z.

Mountains/Deserts...Mostly clear skies with unrestricted VIS through
this morning. Increasing clouds above 15000 feet MSL today, with
cumulus near 10000 feet possible over the mountains 18-01Z.

&&

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

&&

.BEACHES...
A moderate period south-southwesterly swell (2-3 feet at 15-16
seconds) will generate elevated surf and a high risk of rip currents
today and Thursday. Surf of 3-5 feet expected with sets to 6 feet
possible, primarily on southerly facing beaches. Swell and surf will
begin to lower on 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/BEACHES...CSP