206
FXUS66 KSGX 051824
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1124 AM PDT Fri Jun 5 2026

.SYNOPSIS...
Warm today with high temperatures a few degrees above normal.
Cooler over the weekend with more widespread marine layer low
clouds. Elevated southwest to west winds during the afternoon and
evening through the weekend. Minor daily temperature fluctuations
Monday through Thursday of next week, with the potential for more
significant warming late in the week. Night and morning low clouds
will continue for the coastal areas and valleys.

&&

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

...Updated Aviation and Marine discussions...

Marine layer low clouds have filled in over the coastal areas and
spread into inland Orange County and parts of the San Diego County
Valleys, with clear skies elsewhere. Low clouds will spread
slightly further inland through sunrise, potentially reaching the
far west parts of the Inland Empire, before clearing back to the
coast by late morning. Weak upper level ridging remains over the
region today, bringing another warm day with high temperatures
in the low to mid 70s along the coast, upper 70s to low 80s for
inland Orange County and the western valleys, mid 80s to low 90s
in the inland valleys, 80s in the mountains, upper 90s in the high
desert, and around 105-108 in the low deserts.

An upper level low currently off the coast of British Columbia
will move southeast into the Pacific Northwest and amplify into
Saturday, with a reinforcing low following a similar path Sunday
into Monday. This will bring cooling across the region into the
weekend with highs lowering to a few degrees below normal by
Sunday. The marine layer deepens each night with low clouds and
patchy fog spreading further inland, potentially covering much of
the inland valleys by Sunday morning. This will also generate
breezy southwest to west winds in the mountains and deserts where
gusts will be near 35-45 mph during the afternoons and evenings,
strongest on Saturday.

While troughing remains around through the middle of the week, the
upper trough becomes less amplified, allowing for minor warming
across Southern California. Temperatures fluctuate slightly each
day, but in general remain within a few degrees of normal. The
marine layer becomes more shallow for less widespread night and
morning low clouds. Ensembles remain in fairly good agreement with
some form of troughing through Wednesday. By Thursday, around 55%
of the members keep the trough over the western US, while the
remaining members are more progressive and have the trough
shifting eastward, allowing some ridging to move in from the west.
This continues into Friday and Saturday, though as we get later
into the week the upper ridge becomes the slightly more dominant
solution, comprising around 58% of the ensemble space. The trough
lingering would result in a continuation of cooler weather with
highs around normal, while the ridging solution would result in
more warming and less low clouds as we head into the end of the
week.

&&

.AVIATION...
051800Z...Coast/Valleys...Low clouds based 1100-1500 ft MSL with
tops to 2000-2200 ft are lingering along the coastal region, where
it will see only partial/intermittent clearing today, especially in
southern San Diego Co. Low clouds will spread inland again after 00Z
and spread more fully inland overnight into Saturday, including into
parts of the Inland Empire. Bases/tops will be a bit higher at 1400-
1800 ft with vis 4-6 SM for inland edge of clouds in valleys/Inland
Empire. Clouds will struggle to clear from coastal regions again Sat
morning.

Mountains/Deserts...Expect clear skies and VFR conditions today,
with increasing clouds above 20000 feet tonight. Southwest-west
winds will increase in the mountains and deserts with gusts reaching
30-40 knots after 21Z, the decrease after 03Z tonight. MOD
up/downdrafts and pockets of LLWS in lee (north and east) of
mountains. Similar winds Sat afternoon and evening.

&&

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

&&

.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...CSP

NWS San Diego (SGX) Office