San Diego Weather at Mission Trails, CA

000
FXUS66 KSGX 211628
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
828 AM PST Tue Jan 21 2020

.SYNOPSIS...
Clouds will break later today, allowing limited sun along and west
of the mountains this afternoon, with a few isolated showers still
possible. After a mostly cloudy night with patchy fog west of the
mountains, skies will become fair on Wednesday, and a warming trend
will begin with daytime temperatures climbing back above average
Thursday through Saturday. By Sunday, another weak Pacific system
will approach with increasing clouds, cooling, and a chance for
light showers Sunday night or Monday.

&&

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

Rainfall was measured over all of San Diego County last night,
tapering to the north, with none recorded over the high desert and
very spotty amounts over SW San Bernardino County. A rainfall
summary has been posted and headlined on our webpage. Radar still
has a few echoes as of 8 AM PST, but the widespread rain has ended.
The forecast was updated for more clouds and a slight chance for
showers continuing, mainly near and along the coastal slopes of
the Riverside and San Diego County mountains.

Satellite imagery shows widespread low clouds persist along and west
of the mountains, and extend over the CA Bight. Another area of
high clouds is drifting SE toward the CWA, which is associated with
a weak trough. The 12Z Miramar sounding had a weak inversion
based near 6K FT with near saturation up through 14K FT with a PW
over just over one inch. Much of that high level moisture has likely
thinned, but not the lower levels, which will remain high through
tonight. Due to the high RH and the approaching weak trough, some
spotty showers will be possible through the day, but mainly along
the coastal slopes.

After we get this next weak trough embedded in the NW flow aloft
past us, a ridge will begin to build over the SW, along with some
weak offshore flow at times. This will set us up for a string of
fair, dry, and warmer days into the weekend. After Saturday, another
weak Pacific trough will approach with some cooling on Sunday, and a
chance for more light showers Sunday night into Monday.

After Monday through much of next week, the pattern returns to
fair and mild, with the majority of both the GFS/ECMWF ensemble
members coming up dry.

&&

.AVIATION...
211630Z...Widespread low clouds with bases around 2500 ft MSL cover
most of the region west of the mtns. Patches of clouds with bases
around 600 ft MSL could impact TAF sites at times. Fog and drizzle
could reduce vis to 3-5 miles at times with higher terrain obscured
in clouds and fog. Partial clearing of low clouds 18-22Z from coast
toward valleys and lastly along mountain slopes. Areas of low clouds
redevelop after 02Z 1500-2000 feet MSL with random coverage across
the coastal basin.

&&

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

&&

.Beaches...
Swell and surf will build late today through Wednesday, generating
surf of 4-6 feet along portions of southern San Diego County on
Wednesday. The higher sets, along with a long swell period, will
create strong rip currents and hazardous swimming conditions.
&&

.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...10
AVIATION/MARINE/BEACHES...PG