979
FXUS66 KSGX 152347
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
447 PM 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...

...UPDATED AVIATION DISCUSSION...

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...
160000Z...Coast/Valleys...Low clouds based around 2200-2800ft MSL
move to the coast around 01-02z, pushing inland after 03z and
filling in most of the coastal basin by 06z. Expect clouds to push
into the Inland Empire after 05z, widespread by 10z. Patchy drizzle
for coastal sites early Wed morning with intermittent minor 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. FEW cu AOA 25,000ft MSL near mountain peaks this evening
and again Wednesday afternoon.

&&

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

&&

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

&&

$$

PUBLIC...APR
AVIATION/MARINE...Zuber