760
FXUS66 KSGX 211834
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1134 AM PDT Thu May 21 2026

.SYNOPSIS...
A weak area of low pressure will linger over the area through
Monday, bringing temperatures near to slightly above normal with
night and morning clouds and fog for the coastal and western valley
areas. A stronger area of low pressure moves by from the north,
bringing cooler and breezier weather by the middle of next week. A
subtle warming trend with less wind will occur for the latter part
of next week.

&&

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

Similar weather from yesterday will occur today as a weak trough is
draped over the region. A slight increase in onshore flow on Friday
will bring slightly cooler weather to areas west of the mountains
with valley regions cooling up to 5 degrees. This pattern will also
bring greater cloud development across the coast and far western
valleys of Orange and San Diego Counties, potentially into the
Inland Empire, by Friday morning. The forecast will remain pretty
similar into the holiday weekend as the weak trough stays over
the region with temperatures near average with weak onshore winds.
Low clouds will continue to move into coastal and valley areas of
Orange County and San Diego County each night and morning, some
of which may venture into the edges of the Inland Empire.

By Monday, a stronger area of low pressure will move into the
Pacific Northwest. Model guidance is a bit split on how far south
this system will go into the first half of next week. Though no
precipitation is expected for SoCal, the levels of cooling and
wind will be determined by the system`s position. The farther
south this goes, the greater the cooling and windy weather will
occur. West winds will begin to increase across the mountains and
the deserts by next Monday afternoon, peaking in strength on
Tuesday. NBM models show winds gusting near 30-45 MPH across most
mountains and deserts. East-west oriented passes in Riverside and
San Diego Counties will see the highest winds with gusts at or
above 60 mph at times. The low pressure system will eventually
push east sometime around next Wednesday or Thursday, bringing
warmer and less windy weather by the end of next week.

&&

.AVIATION...
211630Z...Coast/Valleys...SKC over land areas through this afternoon
with low clouds lingering just offshore. Cigs to move ashore after
03Z with slightly higher bases (1200-1800 ft MSL). Clouds spreading
northward and into western valleys overnight reaching up to 15-20
miles inland. 30% chance for cigs reaching the western/southern
Inland Empire (including KONT). Clouds scattering to the coast by 17-
18z Fri.

Otherwise, mostly clear and VFR conditions today and tonight.

&&

.MARINE...
No hazardous marine conditions are expected through Tuesday morning.

&&

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

&&

$$

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