Alpine, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

115
FXUS66 KSGX 040504
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1004 PM PDT Sun May 3 2026

.SYNOPSIS...
A low pressure system will approach the region, bringing cooler
and breezier weather, along with a chance of light rainfall
through Tuesday. A deepening marine layer could bring patchy
drizzle to portions of the coastal areas and inland valleys again
tonight into Monday morning. The best chance for light rain
showers will be along and west of the mountains Monday evening
into Tuesday morning. Dry and warmer weather is expected by
Wednesday into next weekend.

&&

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

A cutoff low continues to tumble closer to the California coast
today, bringing a deep marine layer, cooler weather and increased
winds across the mountains and deserts. Winds are currently near
20-35 MPH across these regions and will increase this afternoon
into the evening closer to 35-45 MPH. Winds look to continue to be
gusty into the night with slightly higher winds by Monday
afternoon and evening, where gusts will locally reach above 55 MPH
in some mountain passes in the Riverside and San Diego Counties.
High profile vehicles will see increased risk of incidents in
windy conditions and blowing sand/dust.

The marine layer is around 5,000 feet thick, covering much of the
coastal basin and even reaching into the top of the Cajon Pass.
Clouds will partially clear areas this afternoon, but other areas
will remain under the clouds throughout the day as the low clouds
resurges back inland by later this afternoon/evening. Just like
this morning, areas near the coast may see some marine layer
drizzle/light showers overnight into Monday monday morning as the
marine layer remains quite saturated. The area of low pressure
will move closer to the region by Monday into Tuesday, bringing an
increased chance of light showers from the coast to the mountains.
Hi-res models are in pretty fair agreement on the timing of the
light showers to begin around Monday evening, becoming more
widespread overnight into Tuesday morning. Areas of San Diego
County have the best chance to see rainfall. The showers will be
scattered in nature, with some areas seeing over a quarter of an
inch and others minimal totals to none. The core of low pressure
system moves to the east later on Tuesday, where residual showers
may linger across the mountains into the afternoon with partial
clearing closer to the coast.

This system will also bring much cooler weather. Monday and
Tuesday will be the coolest days of the upcoming week with
highs only reaching the 40s to near 50 degrees in the mountains
and highs in the 60s for areas west of the mountains into the
high desert. Comfortable 70s will take hold across the Anza
Borrego desert into the Palm Springs area.

&&

.AVIATION...
040600Z....Coast/Valleys...Mid level clouds based ~4500ft MSL
currently SCT-BKN across the coastal basin this afternoon will
become more BKN-OVC into this evening. An initial wave of widely
scattered VCSH becomes possible starting after 06z Monday, ending by
15-18z. This VCSH will likely be accompanied by a lower layer of
clouds near 2000-3000ft, which may bring brief CIGs overnight (20-
40% chance). Lower level clouds departing with the VCSH by 18z, with
the mid level clouds (~4500ft MSL) becoming more SCT-BKN again.

.Mountains/Deserts...Strong winds this evening are starting to
slowly weaken this evening with widespread gusts into the deserts of
25-30 kts, locally up to 40 kts along desert mountain slopes and
through mountain passes. Winds gradually weakening between through
12z, remaining elevated through passes before picking back up after
21z Monday with similar strength gusts to today.

Additionally, coastal mountain slopes locally obscured between 4000-
6000 ft MSL in BR with clouds intersecting terrain. These clouds
will increase in coverage after 03z Monday, become less numerous by
18z.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from 8 AM to 9 PM PDT Monday for Apple and Lucerne
     Valleys-San Gorgonio Pass near Banning.

PZ...None.

&&

$$

PUBLIC...Zuber
AVIATION/MARINE...Munyan