Rancho Santa Margarita, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

366
FXUS66 KSGX 122027
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
127 PM PDT Tue Aug 12 2025

.SYNOPSIS...
Above average temperatures will continue for inland areas through
Wednesday with a gradual cooling expected Thursday through Saturday.
A warming trend will return for early next week. Breezy westerly
winds expected on the desert mountain slopes into the deserts each
afternoon/early evening. Low clouds will be persistent for the coast
and western valleys each night and morning, becoming more widespread
Friday into the weekend.

&&

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

At 1 PM, temperatures were running up to 5 degrees cooler than this
time yesterday for the inland valleys, with some places along the
coast a degree or two warmer. The low deserts are 2 to 5 degrees
cooler than this time yesterday. Highs tomorrow are expected to be a
few degrees cooler than normal for most places west of the
mountains, but still up to 5 degrees above average for the deserts.
Low clouds this afternoon are locally lingering at area beaches. Low
clouds and fog are expected to spread back inland overnight,
reaching into the western valleys.

An upper level trough will settles over the West Coast on Thursday.
The trough is expected to remain in place into early next week. This
will result in below average temperatures for the end of the week
along with breezy westerly winds on the desert mountain slopes into
the deserts and a deeper marine layer.

Early next week the ridge of high pressure to our east may begin to
strengthen and move back towards Southern California. That will
bring another round of gradual warming Sunday through Tuesday. There
remains some uncertainty in the position of the ridge as it settles
over the desert southwest. The overall position of the ridge will
determine how hot it will get and if any monsoonal moisture will be
allowed into our area. Latest ensemble guidance does not have any
precipitable water increases or notable precipitation chances until
at least the end of next week.

&&

.AVIATION...
122030Z...Coasts/Valleys...Other than patchy low clouds on the
immediate coast, VFR conditions prevail. Clouds based 800-1200 feet
MSL develop at the coast and start to push back ashore by 02-04z
Wednesday, building 10-15 miles inland. For western valleys and
higher coastal terrain, VIS 2-5SM, locally lower, possible after
midnight through 14z Wed. Clouds scatter out 16-18z.

Mountains/Deserts...Mostly clear and VFR conditions continue through
Wednesday.

&&

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

&&

.BEACHES...
Long period (15-16 second) southwesterly (200-220 degree) swell will
bring elevated surf and a high rip current risk through Thursday.
Surf of 3 to 5 feet with local sets 6 to 7 feet.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Extreme Heat Warning until 8 PM PDT this evening for Apple and
     Lucerne Valleys.

     Extreme Heat Warning until 8 PM PDT Wednesday for Coachella
     Valley-San Diego County Deserts-San Gorgonio Pass near
     Banning.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE/BEACHES...Westerink