143
FXUS66 KSGX 300524
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1024 PM PDT Mon Jun 29 2026

.SYNOPSIS...
Increased winds over the mountains and deserts this afternoon into
Tuesday morning. A deep marine layer and well below average
conditions will prevail through the middle of the week. A gradual
warming is expected into the 4th of July holiday weekend, with
conditions warming to near or slightly above normal by early next
week.

&&

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

...UPDATED AVIATION DISCUSSION...

The overall pattern will remain troughy through Friday, with another
shortwave expected to move through the mean flow tomorrow. This will
increase the onshore pressure gradient, maintaining a deeper
marine layer, elevating winds, and maintaining below average
temperatures. Additionally, patchy drizzle is possible tonight
into Tuesday morning. Peak winds for the mountains, deserts, and
passes this afternoon into Tuesday morning will be 35 to 50 mph.
Gusts up to 60 mph possible through San Gorgonio Pass.

Conditions will gradually warm each day through the holiday weekend,
but highs through Wednesday for inland areas will be 10 to 20
degrees below average. For the 4th of July there is more confidence
in weak ridging developing over the US West Coast, with more
uncertainty in the strength and placement of the ridge into early
next week. Even with ridging aloft this weekend, highs in and west
of the mountains will be 1 to 5 degrees below average, with highs in
the deserts up to 3 degrees above average.

The marine layer will stay deep through mid-week becoming shallower
and more confined to the coast and western valleys for Friday into
early next week.

&&

.AVIATION...
300515Z....Coast/Valleys/Foothills...Low clouds with bases
2000-3000 ft MSL and tops to 3500 ft MSL will continue to fill in
across the coastal basin through 09Z. 10-20% chance of patchy
drizzle 09-18Z, with the greatest chances near the coast. Clouds
scatter out 16-19Z Tuesday. Low clouds will redevelop at the
coastal areas 23-04Z with bases/tops around 1800-2500 ft MSL,
spreading into the inland valleys again Tuesday night.

.Mountains/Deserts...Southwest to west winds with surface gusts
20-40 kts with local gusts to 50 kts through the passes. Winds
slowly weaken 08-12Z, then strengthen again around 22-00Z. Gusts
around 20-35 kt, locally to 45 kt in the passes Tuesday afternoon
into Tuesday night. MOD- STG up/downdrafts and pockets of LLWS
over and east of the mountains.

&&

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

&&

.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...CO
AVIATION/MARINE...SS