047
FXUS66 KSGX 211053
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
353 AM PDT Tue Apr 21 2026

.SYNOPSIS...
Cooler through Wednesday with strong gusty southwest to west
winds for the mountains and deserts gusting to 40 to 50 mph for
this afternoon and night with isolated gusts to 65 mph. There is a
chance of light showers for late this afternoon through this
evening from a weakening cold front. It will be dry with seasonal
temperatures for Thursday and Friday, then cooler and breezy for
the weekend with a chance of showers from the coast to the
mountains.

&&

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

.SHORT TERM (Today through Thursday)...
A low pressure system will move inland through California tonight
and Wednesday with a weakening cold front moving through
southwestern California this evening. Onshore flow will strengthen
with stronger and gusty southwest winds for the mountains and
deserts into Wednesday evening. The strongest winds are expected
for this afternoon and night with gusts to 40 to 50 mph and
isolated gusts to 65 mph.

There is a chance of mostly light showers from the coast to the
mountains from the weakening cold front, mainly between between 4
PM and midnight. Rainfall could range from little or no
measurable rainfall near the coast to as much as one-tenth to one-
quarter in for the mountains of San Bernardino and Riverside
Counties with one-tenth inch or less in the San Diego County
mountains. The snow level will rise to 8000 to 8500 feet for late
this afternoon, then fall to 5000 to 6000 feet by Wednesday
morning with one inch or less of snowfall above 7500 feet.

High temperatures for today will be as much as 5 to 10 degrees
cooler for the mountains and high desert with most areas another
few to around 5 degrees cooler for Wednesday. With the cooling,
high temperatures on Wednesday will be near average at the coast
to as much as 5 to 10 degrees below average for the mountains.
High temperatures on Wednesday will be mostly in the mid 60s to
lower 70s for the coast and valleys with the lower deserts in the
lower to mid 80s. Drying and warmer with weaker winds for
Thursday with high temperatures around average.

&&

.LONG TERM (Friday through Monday)...
High temperatures will remain around average for Friday. A low
pressure system off the California coast on Friday will move
inland into central and southern California for the weekend
bringing cooling, stronger and gusty southwest to west winds for
the mountains and deserts, and a chance of showers at times from
the coast to the mountains. Timing is uncertain, but amounts are
expected to be generally light, one-tenth inch or less at the
coast to one-quarter inch or less in the mountains.

High temperatures for the weekend will be near average at the
coast to 5 to 10 degrees below average for the mountains on
Saturday and 10 to 15 degrees below average on Sunday. High
temperatures for the weekend will be mostly in the 60s to around
70 for the coast and valleys and in the lower to mid 80s for the
lower deserts on Saturday and in the mid 70s to lower 80s for the
lower deserts on Sunday.

Drying and warmer for next Monday, but with high temperatures for
inland areas still a few to around 5 degrees below average with
high temperatures ranging from the mid to upper 60s near the coast
to the lower to mid 70s for the Inland Empire with the lower
deserts in the mid to upper 80s.

&&

.AVIATION...
210930Z...Coast/Valleys...Patchy low clouds should increase across
the coastal basin, but not achieve uniform coverage this morning.
When and where they occur, cigs will be based around 1800-2200 feet
MSL with tops to 2700 feet. Any cigs should scatter out by 16-17Z. A
band of low clouds based 1500-2500 feet MSL associated with a weak
front containing -SHRA will move from west to east across the
coastal basin from 22-07Z. ISO -SHRA could briefly create MVFR vis.
Clouds mostly clear out from northwest to southeast after that band,
first at Orange County coast and last inland San Diego County.

Mountains/Deserts...Southwest to west winds increase after 21Z with
gusts 35-55 kts, strongest on ridgetops, along desert slopes, and
through mountain passes. Isolated vis reduced by BLDU in the deserts
and moderate/strong up/downdrafts in lee of mountains.

&&

.MARINE...
Westerly winds will increase Wednesday afternoon through Wednesday
night with gusts 20-25 knots likely for outer coastal waters. These
winds could generate choppy and hazardous conditions. Otherwise, no
hazardous marine conditions are expected through Saturday.

&&

.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 7 AM PDT Wednesday for
     Apple and Lucerne Valleys-Riverside County Mountains-San
     Bernardino County Mountains-San Diego County Deserts-San
     Diego County Mountains-San Gorgonio Pass near Banning.

PZ...None.

&&

$$

PUBLIC...17
AVIATION/MARINE...MM

NWS San Diego (SGX) Office