766
FXUS66 KSGX 112049
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
149 PM PDT Fri Jul 11 2025

.SYNOPSIS...
Slightly cooler conditions today and Saturday with a subtle
rebound in temperatures for Sunday and Monday. Gradual cooling
back to near average for mid July expected through the middle-end
of next week with perhaps some monsoonal moisture spreading into
the region. Night and morning coastal low clouds will spread into
the western valleys late each night.

&&

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

This weekend into Monday...

The upper level ridge fueling the heat wave that most are on the
other side of now has slid southwest compared to yesterday, allowing
for many locations to be about 5 cooler than yesterday. This
morning`s coastal eddy helped push a healthy marine layer inland and
with the strong subsidence inversion in place under the ridge,
these clouds have stuck around along most of the beaches/coast
this afternoon. With this, highs this afternoon should stay in the
low 70s along the coast, with upper 80s to mid 90s for the inland
areas, 70s to 80s for the mountains, and the deserts staying hot
- around 110-115 degrees.

The upper ridge becomes more centered just off the southern
California coast by Saturday before it broadens and strengthens some
for Sunday into Monday. With this setup, Saturday will be a touch
cooler than today, with Sunday/Monday warming back up to what we are
seeing today. The marine layer stays fairly consistent each
night/morning, with about 15 miles of inland extent and about 2000ft
deep.

Mid-late next week...

For Tuesday onward, a somewhat complicated pattern sets up where the
ridge splits and slides back eastward to the Four Corners while a
disturbance rounds the southern periphery of this ridge. This is a
highly volatile pattern and model guidance run to run consistency is
quite low. While the exact track of this disturbance is very
uncertain, what appears most likely in this setup will be a
gradual cooldown, bringing high temperatures back to near average.
Mid-level moisture would likely accompany any disturbance rounding
the south-southwestern periphery of the ridge, and if the timing
of some synoptic instability aligns, monsoonal thunderstorms may
be possible in the mountains sometime late next week. There is
only about a 5-10 percent chance of any precipitation and
uncertainty is very high, so stay tuned to see how this pattern
evolves as we get closer.

&&

.AVIATION...
112000Z....Coast/Valleys...BKN low clouds 1200-1500 ft MSL are
continuing to hug the immediate coast, including KSAN. This will
continue for much of the day, before cigs slide back onto land after
01Z Sat about 15 miles inland with high terrain obscured in
clouds/fog. Increasing chance for more clearing toward the coast 18-
20Z Saturday with TAF sites clearing 17-19Z.

Mountains/Deserts...VFR conditions and unrestricted VIS through
this weekend.

&&

.MARINE...
No hazardous marine conditions expected through the middle of next
week.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.

&&

$$

PUBLIC...Munyan
AVIATION/MARINE...APR