Alpine, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

737
FXUS66 KSGX 251206
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
506 AM PDT Sat Apr 25 2026

.SYNOPSIS...
Cool and windy this weekend with chances of light precipitation.
Warmer early next week, then minor cooling and a slight chance of
precipitation towards the middle of the week. Warmer and drier for
the end of the week.

&&

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

New Aviation and Marine Discussion...

Today through tomorrow night...

In the short term, the forecasts remains on track with an
approaching low pressure system, which is going to allow for an
increase of westerly winds, along with a chance of showers,
especially for the coastal-facing slopes. The marine layer is
becoming more dispersed this morning, with the passage of mid to
high level clouds overhead. There could be some patchy areas of
drizzle this morning, especially along the foothills. By later in
the day, there will be an increase of onshore flow, and developing
showers over the inner waters of the SoCal bight, which will move
onshore by later this afternoon and throughout the evening, and on
into tomorrow. The overall low to mid-level flow will bring about
the best chances and highest rainfall rates for the western-facing
slopes within San Diego County. As of now, the best rainfall rates
of possibly up to near an inch will look to occur around the Palomar
Mountain area through Monday. Showers will taper off a bit going
into Sunday, although there will still be enough forcing overhead to
result in a few isolated showers developing throughout the
afternoon. Winds will also continue to increase and become rather
strong and gusty by later in the day, especially for the higher
elevations, where gusts of 45 to 55 mph are expected by later this
afternoon. Strongest winds will occur along the desert slopes, and
through the mountain passes and canyons. There could also be
occasional gusts of up to 65 mph. Blowing dust will also be
possible for the areas with the strongest winds across the deserts,
mainly within the Coachella Valley. Temperatures will also be on
the chilly side for this weekend, and generally running around 5
to 15 degrees below the seasonal average for this time of year for
most locations.

Monday through Friday...

On Monday, there may still be a few lingering showers with
continued onshore flow and a weak perturbation that will be
propagating into the trough could enhance the development of these
showers, otherwise conditions will begin to dry out. The overall
longwave pattern shows a cut-off low becoming positioned well west
of the region over the Pacific Ocean, however, depending on the
track of this system as it begins to transition easterly could
allow for there to be some showers, and possibly a few
thunderstorms, developing by later in the evening on Wednesday and
into Thursday as a possible track with one of the deterministic
members has this U/L low passing just to the south of San Diego,
over northern Baja California, by around Noon on Thursday. This is
still subject to change, being that it is quite a few days out
and that it is a cut-off low, which is a more difficult track to
predict. Besides this, there will overall be a slight warming
trend occurring throughout the week, with relatively drier
conditions through the end of next week.


&&

.AVIATION...
251200Z...Coast/Valleys...BKN/OVC low clouds based 1500-4500ft MSL
have filled in from the coast and valleys and into the Inland
Empire. Scattered to isolated light rain will be possible overnight
and into the morning near coastal areas. Chances for rain will
increase after 21Z from the northwest to the southeast and last
through the end of the TAF period. Cloud bases will lower to MVFR
cigs in and around -SHRA. Winds are expected to get breezy after 15Z
along the coast and move inland after 19-20Z. Expect wind speeds 10-
15 kts with gusts up to 20-25kts.

Mountains/Deserts...Gusty winds out of the west this afternoon
expected to reach 30-40 kts, locally up to 50 kts. Moderate
up/downdrafts will be possible in lee of mtns. Areas of BLDU (3-5SM)
along desert slopes and locally into deserts. After 19z, gusts in
the desert valleys could periodically exceed 35 kts, including vcnty
KPSP.

Rain will reach mtns around 01z Sun with intermittent SHSN above
6500-7000 ft MSL. Mtns shrouded in FG; vis 0-5SM in FG/SHSN.

&&

.MARINE...
No hazardous marine conditions are expected through Wednesday,
though brisk westerly winds 15 to 20 kts are expected this afternoon
and evening through Sunday.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from 2 PM this afternoon to 11 AM PDT Sunday for
     Apple and Lucerne Valleys-Coachella Valley-San Diego County
     Deserts-San Gorgonio Pass near Banning.

PZ...None.

&&

$$

PUBLIC...Stewey
AVIATION/MARINE...Villafane