203
FXUS66 KSGX 151852
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1152 AM PDT Tue Sep 15 2026

.SYNOPSIS...
Area temperatures will be up to 10 degrees below average through
Thursday as an area of low pressure moves over the area. This
pattern will bring night and morning low clouds for areas west of
the mountains with breezy winds across the desert slopes and deserts
each day. A troughing pattern will remain into the weekend and early
next week, where temperatures will rise closer to normal.

&&

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

An area of low pressure is beginning to form near Seattle and
Vancouver. This system will work its way southward through Thursday,
bringing in cooler than average temperatures, breezy conditions
across the mountains and deserts, and a healthier marine layer. Low
clouds will fill in much of the coastal basin each night and morning
with patchy fog on higher terrain. Models hint that the atmosphere
may be moist enough to produce some areas of drizzle Wednesday
morning within 10-15 miles of the coast.

Models pinpoint the low moving as far as Northern California by
Thursday. This will bring temperatures down near 5 to 10 degrees
below normal for inland areas. Chances continue to increase to see
highs near 85 or cooler for areas of the High Desert, Inland Empire
and Inland San Diego Co valleys on Wednesday and Thursday. Sea
breeze winds will increase over desert passes and deserts as well
each afternoon, primarily between 20 and 40 MPH.

The low lifts out of the State and into the Northern Rockies by
Friday into the weekend. This will lead to subtle warming by Friday
into Saturday as a quick and weak area of high pressure nudges into
the region. High temperatures will respond by increasing slightly
and emerging closer to normal by Saturday. Models are beginning to
come into better agreement of a weaker area of low pressure moving
over the area by early next week. This would begin to cool the
region by a few degrees, giving us near to slightly below average
temperatures once again.

&&

.AVIATION...
151800Z...Coast/Valleys...Remaining low clouds over coastal areas
will clear out within the next hour or so. SKC and VFR for this
afternoon. Low clouds based 1900-2400 ft MSL push back ashore 00-02z
Wed in San Diego County and 02-04z in Orange County. Clouds quickly
fill the coastal basin overnight. Patchy drizzle for coastal sites
early Wed morning with intermittent minor cig/vis reductions
possible. Clouds scatter back to the coastline 16-19z, though patchy
low clouds may linger through Wed afternoon near the coast.

Mountains/Deserts...Mostly clear and VFR conditions today and
tonight.

&&

.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...APR
AVIATION/MARINE...KW