Quail Valley, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

671
FXUS66 KSGX 141651
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
851 AM PST Sun Dec 14 2025

.SYNOPSIS...
Areas of dense fog on the coastal mesas and western valleys this
morning and again tonight into Monday morning. Well above normal
high temperatures through Thursday, with periods of weak offshore
flow through Tuesday. Gradual cooling with more widespread night
and morning low clouds and fog for Friday into next weekend.

&&

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

A shallow marine layer with a weak upper level trough has brought
widespread low clouds to the coastal areas and portions of the
western valleys. Areas of dense fog covers the coastal mesas and
elevated terrain in the western portions of the inland valleys.
The fog will likely begin lifting by 9 am the low clouds will
mostly clear to the coast by late morning. The marine layer
inversion is quite strong and is unlikely to weaken much so we
could see low clouds lingering at the coast into the afternoon.
Otherwise, we can expect variable high clouds with hazy sunshine
inland and at the coast after the low clouds and fog clear. The
marine layer presence will moderate temperatures near the coast
but inland high temperatures today will likely be 10 to locally 20
degrees above seasonal averages.


This pattern of low clouds and fog will likely repeat for tonight
into Monday morning even as the upper level trough moves eastward
into AZ. After the upper trough moves east, high pressure aloft
begins to build in from the west and offshore flow develops on
Monday, with winds gusting to around 30 mph below the passes and
canyons. Weak offshore flow under high pressure aloft will persist
into Tuesday and mitigate or nullify the influence of the marine
layer so that low clouds and fog are unlikely to return for Mon
night/Tue morning or Tue night/Wed morning. It will also bring
drier and warmer conditions into the coastal areas, resulting in
daytime high temperatures on Tuesday as much as 10 degrees above
seasonal averages in the coastal areas, and up to 20 degrees above
average in the far inland valleys. Tuesday is likely to be the
warmest day overall, with high temperatures reaching the 80s in
the inland valleys and lower deserts.

Onshore flow returns on Wednesday as a shortwave trough moves
inland to the north and the upper level ridge weakens and flattens
out. This could bring some cooling to the coastal areas and far
western portions of the inland valleys, and potentially a return
of low clouds and fog to the coastal areas Wed night. However,
this is a fast-moving trough and offshore flow quickly returns on
Thursday as a sfc high follows the departing trough into the Great
Basin. The offshore winds will bring drier and warmer conditions
but are unlikely to be strong enough to produce any other impacts.

As we approach next weekend, a more vigorous trough will displace
the upper high to the south, establishing a high-zonal pattern
over CONUS. This pattern is expected to bring a weak atmospheric
river to central and northern CA next weekend but SoCal will
likely remain dry but cooler with more of a marine layer presence
as onshore flow returns. Temperatures for next Sat and Sun will
range from near normal at the coast to about 10 degrees above
normal in parts of the inland valleys.

&&

.AVIATION...
141630Z...Coast/Valleys...Low clouds based 300-800ft MSL that
pushed into the western inland valleys, including the western Inland
Empire remain in place this morning and have yet to erode much.
Widespread VIS reductions down to 2-5SM for coastal areas with
VIS 0-2SM in FG over elevated coastal terrain and inland areas along
the I-15 corridor. VIS should gradually improve through 18-19z as
clouds lift some and begin to erode, though IFR CIGs and 4-6SM VIS
in BR/HZ likely to persist through 19-20z along the coastal areas.
Clearing of clouds will occur for much of San Diego County by 19-
20z, 20-21z for Orange County, with stratus lingering at
portions of the immediate coast through the afternoon. Low clouds
with slightly higher bases (about 400-900ft MSL) push inland again
as early as 00-02z Monday for SD County, and after 04z for Orange
County. VIS to drop to 0-3SM for inland areas when low clouds
approach, lowering gradually to 2-5SM for coastal sites.


Mountains/Deserts...Clear skies and VFR conditions expected through
the Monday morning.

&&

.MARINE...
Low clouds and mist with visibility generally above 1 nautical mile
will continue into early Sunday afternoon. Otherwise, no hazardous
marine conditions are expected through Thursday.

&&

.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...PG
AVIATION/MARINE...Munyan