483
FXUS66 KSGX 272047
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
147 PM PDT Thu Mar 27 2025

.SYNOPSIS...
Cool weather will continue for much of the next week with a deeper
marine layer. The marine layer will be deep enough to produce
areas of drizzle at times the next few mornings. Winds will
continue to be elevated across the mountains and deserts for much
of the next week as well. The pattern starts to begin to favor
notable precipitation chances for areas along and west of the
mountains by next Wednesday and Thursday.

&&

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

Low clouds have begun to scatter for some areas west of the
mountains, though not as much across the northern Inland Empire.
Brief sunshine will make an appearance this afternoon before low
clouds surge back inland across much of the coastal basin this
evening. The marine layer will maintain a deep presence over the
next couple of nights, where drizzle will be possible. Winds are
near 30-45 MPH across some E-W passes this afternoon. Latest hi-
res guidance shows winds increasing and expanding into the deserts
this evening and overnight where winds have around a 25-40% chance
of reaching 55 mph in favored passes. Cooling will continue to
push inland on Friday, with highs only making it into the 60s
across the high deserts and highs near 80 degrees in the Coachella
Valley.

The weekend will be quite similar to Friday. A deep marine layer
will persist, so expect low clouds for much of the mornings with
some partial clearing for area west of the mountains. Breezy but
sunnier weather will continue for higher elevations and desert
areas. Winds look to let up the most on Saturday, where winds will
be more confined to the mountain areas. Temperatures will continue
to be around 5 degrees cooler. Model projections diverge by
Tuesday through Thursday, as the influence of ridge to the south
is in question. A series of troughs to the north will try to
maintain the cooler than normal and breezier pattern but the ridge
to the south may bring more influence. NBM was used for now, which
leans toward a cooler and windier pattern. Depending on how far
the troughs push south, we may see a notable chance for light rain
showers (25-45% chance) mainly along and west of the mountains.
Model ensembles show wettest solutions later on Wednesday into
Thursday. The forecast for this time period still has a lot of
uncertainty so things will continue to evolve as we get closer in
time.

&&

.AVIATION...
272045Z...Coast/Valleys/Foothills...Low clouds from this morning
have cleared out nicely for San Diego County with some lingering
cumulus-stratocumulus across northern Orange County and the northern
Inland Empire. Bases of these clouds are at 2500-3500ft MSL with
tops to ~4000ft. Low clouds begin to fill back in across the coastal
basin after 00z this evening, becoming widespread after 02-04z.
Bases this evening and tonight will likely be lower than this
morning, with a 85% chance of bases below 3000ft MSL. There is a 20%
chance of CIGs less than 2000ft through 12z this evening, with bases
likely lifting back to 2500-3500 after 12z.

Higher Mountains/Deserts...FEW-SCT high clouds above 20000 feet MSL.
Westerly winds over the ridges strengthen and spread through the lee
slopes into deserts this afternoon/evening, with gusts 30-50 kts.
Winds persist through Saturday. Areas of moderate up/downdrafts in
lee of mountains.

&&

.MARINE...
Northwesterly winds pick up this afternoon and continue to increase
through the overnight hours. By early Friday, 15-20 kt winds with
gusts to 25 kts are expected to persist through Saturday morning.
Winds decrease some by noon Saturday, but gusts remain elevated to
15-20 kts into Sunday morning. Elevated winds look to return on
Tuesday.

Seas increase early Friday to 6-11 feet in the outer coastal waters
with occasional short periods of 7-9 seconds, diminishing throughout
the day Saturday. Small Craft Advisory remains in effect as choppy
seas and hazardous boating conditions are likely. See the Small
Craft Advisory for more details.

&&

.BEACHES...
Elevated surf 4-6 feet, with local sets to 7 feet on west-facing
beaches, and high rip current risk expected Friday and Saturday.

&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 5 AM Friday to 5 AM PDT Saturday for
     Waters from San Mateo Point to the Mexican Border Extending
     10 to 60 nm out including San Clemente Island.


&&

$$

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