Rancho Santa Margarita, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

892
FXUS66 KSGX 260959
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
259 AM PDT Tue May 26 2026

.SYNOPSIS...
The marine layer will continue to slowly deepen to around 5000
feet for early Wednesday. There could be some drizzle or light
rain from this deep marine layer at times, mainly late at night
into the morning into Thursday morning. High temperatures will
lower several degrees for Tuesday and Wednesday to as much as 20
to 25 degrees below average for the mountains on Wednesday.
Southwest to west winds in the mountains and deserts will
strengthen for this afternoon through Wednesday night, with gusts
of 40 to 50 mph with isolated gusts to 70 mph through the passes.
There will be warming for Friday through next weekend with the
marine layer becoming shallower.

&&

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

.SHORT TERM (Today through Thursday)...
A closed low pressure system will move across western Oregon today
and into California and Nevada for Wednesday and Thursday before
beginning to weaken and move east on Friday. High temperatures
for today will cool as much as 10 to 15 degrees today for some
inland areas and as much as another 5 to 10 degrees on Wednesday
for the mountains and deserts. With the cooling, high temperatures
for the mountains on Wednesday will be as much as 20 to 25
degrees below average. High temperatures on Wednesday will be
mostly in the 60s for the coast and valleys and in the upper 70s
to mid 80s for the lower deserts with the mountains mostly in the
40s and 50s and the high desert in the 60s.

Satellite imagery shows coastal low clouds extending well inland
across San Diego County onto the coastal slopes of the mountains
and spreading northward across the Inland Empire and Orange County
with low clouds spreading through the Cajon Pass. The marine layer
will continue to slowly deepen to around 5000 feet for early
Wednesday. There could be some drizzle or light rain from this
deep marine layer at times, mainly late at night into the morning
into Thursday morning.

Onshore flow will be stronger for today and Wednesday with
southwest to west winds for the mountains and deserts gusting to
40 to 50 mph at times with gusts to 70 mph in the northern
Coachella Calley below the San Gorgonio Pass for this afternoon
through Wednesday night.

&&

.LONG TERM (Friday through Monday)...
The warming trend will continue through the weekend into early
next week. High temperatures of 5 to 10 degrees below average for
inland areas on Friday will warm to 5 to 10 degrees above average
for Monday of next week. High temperatures on Friday will range
from the mid to upper 60s near the coast to the 70s for the Inland
Empire with the lower deserts around 90. For Monday of next week,
high temperatures will range from the lower 70s near the coast to
the mid 80s to mid 90s for the Inland Empire with 102 to 106 for the
lower deserts. Night and morning coastal low clouds will spread
into portions of the inland valleys for early Friday and early
Saturday, then only into the western valleys for early Sunday and
early Monday.

&&

.AVIATION...
261200Z...Coast/Valleys/Foothills...Low clouds with bases 2500-
3000ft MSL have filled in across the coastal basin this morning
through to the coastal mountain foothills. Patchy -DZ will be
possible around 13-18z as the marine layer deepens. Highest chances
will be in areas near the coast. Cloud bases will likely lift
slightly after 17-19Z to 3000-3500ft MSL and scatter out for the
inland valleys. Orange County and portions of coastal San Diego
County may see intermittent scattering in the afternoon, but should
remain more BKN than SCT. Marine layer clouds quickly refill the
coastal basin between 00-06z Wednesday, with bases settling back
down to 2500-3000ft MSL.

Higher Mountains/Deserts...Mostly clear skies and VFR conditions
expected through the TAF period. West to southwest winds will pick
up after 18-19z. Widespread gusts 30-40 kts with isolated gusts to
60 kts through the passes. Winds taper off some between 06-12z
Wednesday, but remain fairly elevated through the overnight hours.

&&

.MARINE...
Winds and seas increase Tuesday afternoon and into early Wednesday,
generating hazardous conditions for small craft in the outer waters,
especially near San Clemente Island. For more details, see the Small
Craft Advisory product. Winds and seas decrease Wednesday night,
with no hazardous marine conditions are expected thereafter 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 3 PM this afternoon to 5 AM PDT Thursday for
     Riverside County Mountains-San Diego County Deserts-San
     Diego County Mountains-San Gorgonio Pass near Banning.

     Wind Advisory from 3 PM this afternoon to midnight PDT tonight
     for Apple and Lucerne Valleys.

PZ...Small Craft Advisory from 1 PM this afternoon to 1 PM PDT
     Wednesday for Waters from San Mateo Point to the Mexican
     Border Extending 10 to 60 nm out including San Clemente
     Island.

&&

$$

PUBLIC...17
AVIATION/MARINE...Munyan