173
FXUS66 KSGX 292344
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
444 PM PDT Sat Aug 29 2026

.SYNOPSIS...
Gradual cooling trend through the middle of the upcoming week. For
Tuesday and Wednesday, increased high cloud cover is likely along
with a 15 to 25 percent chance of light precipitation as moisture
from Tropical Cyclone Karina potentially gets pulled northward. This
tropical system is forecast to remain well to our south. Gradual
warming for the latter half of next week. Night and morning low
clouds will be more widespread for the upcoming week, reaching into
the western valleys at times.

&&

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

...UPDATED AVIATION DISCUSSION...

While high temperatures today will remain 3 to 7, locally up to 12
degrees above average they`re forecast to be 3 to 5 degrees cooler
than yesterday. That cooling trend will continue through Tuesday
or Wednesday for most locations. By Wednesday, high temperatures
are expected to be 3 to 7 degrees below average for this time of
year. Additionally, marine layer low clouds and areas of fog will
become more prevalent along the coast and in the western valleys
at times.

Moisture from Tropical Cyclone Karina may be pulled into Southern
California by mid-week. There is high confidence this will
increase high cloud coverage across the area, with lesser
confidence in chances of light rain. Current forecast has pulled
rainfall chances back for much of Wednesday, leaving the highest
chances on Tuesday at 15-25 percent. Model guidance still is yet
to align on the amount of moisture that moves into our area. The
EC continues to trend drier than the GFS/Canadian. How the
tropical cyclone tracks will ultimately be the biggest influence
in moisture influx, with a more westerly track being drier for us
and a more easterly track being wetter. Current forecast closely
follows the NBM.

Thursday into next weekend, the upper level high begins to shift
back westward, bringing warming and the potential return of monsoon
moisture. High temperatures return to near average by Friday.

&&

.AVIATION...
300000Z...Coast...Patchy low clouds around 500-700ft MSL continue
near the coast, becoming more widespread and moving inland after 06z
Sun. Intermittent CIGs at coastal TAF sites with highest confidence
for a few hours of IFR CIGs at KSAN (70-80%) and KCRQ (50%) by 12z.
There is only about a ~30% chance of CIGs reaching coastal Orange
County (KSNA) for 12-16z. Bases are expected to be around 600-1000ft
MSL. VIS down to 2-5SM for pockets of the coast and valleys, locally
down to 1/2SM for coastal terrain. Any clouds that move inland will
scatter back to the coast by 16-17z, with SKC thereafter.

.Elsewhere...Widespread gusts to 15-25 kts in the mountains and
deserts this evening, locally up to 35 kts within mountain passes.
Gusts weaken after 03z Sun. Otherwise, FEW high cu AOA 20,000ft MSL
generally over mountains.

&&

.MARINE...
Gusts around 20 knots expected each afternoon through Monday in the
vicinity of San Clemente Island. Otherwise, no hazardous marine
conditions are expected through Thursday.

&&

.BEACHES...
A 3-foot swell from the south-southwest (200 degrees) at 15-17
seconds will persist into Sunday. This will bring localized elevated
surf of 3-5 feet with sets to 6 feet, along with a high rip current
risk to southwest-facing beaches, mostly in north San Diego County
and Orange County. A new pulse of southerly swell (180-190 degrees)
from Tropical Storm Karina will keep surf elevated at 3-6 feet for
Monday through Wednesday.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory until 8 PM PDT this evening for Orange County
     Coastal Areas-San Diego County Coastal Areas.

     Extreme Heat Warning until 8 PM PDT this evening for Coachella
     Valley-Orange County Inland Areas-San Bernardino and
     Riverside County Valleys-The Inland Empire-San Diego County
     Deserts-San Diego County Mountains-San Diego County Valleys-
     San Gorgonio Pass near Banning-Santa Ana Mountains and
     Foothills.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE/BEACHES...Zuber

NWS San Diego (SGX) Office