376
FXUS66 KSGX 060616
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1116 PM PDT Sat Sep 5 2026

.SYNOPSIS...
Patchy marine layer low clouds and fog can be expected overnight and
in the morning as high level clouds from Tropical Cyclone Marie move
over the area this weekend. Periods of light to locally moderate
precipitation are possible, highest chances on Sunday. There is a
slight (5-10%) chance of thunderstorms, mainly over the San
Bernardino Mountains and High Desert on Sunday afternoon. Warming
high and low temperatures through the middle of next week. Slight
chance of mountain showers and thunderstorms return for mid-week.

&&

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

...UPDATED AVIATION DISCUSSION FOR 06Z TAF PACKAGE...

Tropical Cyclone Marie is about 800 miles south of San Diego, CA
this morning. A swath of high clouds and moisture from the cyclone
have made their way into Southern California. The only radar returns
over SoCal as of 11 AM were in Imperial County. As Marie continues
to track north and west this weekend, additional moisture will be
pushed into the area increasing chances of showers. The highest
chances are tomorrow north of San Diego County. Total rainfall
amounts may reach over a half an inch over the San Bernardino
Mountains, and generally 0.20 to 0.30 inches for the Inland Empire,
with slightly lesser amounts to the coastal areas of Orange County,
tapering off to lesser amounts over San Diego County. It`s possible
some areas in southern San Diego County may not see any accumulating
rainfall. There is a 5 to 10 percent chance of thunderstorms over
the San Bernardino Mountains and High Desert Sunday afternoon. Drier
conditions expected for Monday and Tuesday.

For this weekend, high temperatures will remain below average inland
with highs near the coast running a few degrees above average.
Overnight lows will also return to above average for this time of
year by Sunday. By Tuesday, high temperatures will be within a few
degrees of average for the mountains and deserts and 3 to 8 degrees
above average for the coast and valleys. Above average low
temperatures will be maintained into next weekend. Widespread minor
to moderate HeatRisk is expected for inland areas Wednesday and
Thursday. Temperatures will peak on Wednesday and gradually cool
into Friday.

The upper level flow turns southeasterly Wednesday and Thursday,
which may allow for some additional moisture to creep into the area.
There still remains some uncertainty in the upper level pattern with
the position of the upper level ridge over the southwestern US and a
trough off the US West Coast. A more easterly position of the trough
would result in drier conditions with a more westerly position of
the ridge allowing more moisture into the area. Current forecast
follows the NBM which has 20 to 40 percent chance of showers and a
15 to 20 percent chance of thunderstorms over the mountains
Wednesday and Thursday afternoon.

&&

.AVIATION...
060600Z...Coast/Valleys/Mountains...Mid/high clouds around 10,000-
20,000ft MSL currently over San Diego and eastern Riverside counties
will continue to move across and spread north to cover the rest of
the area by 10Z. Light showers will be possible at times, mainly in
the mountains, through 12Z. Rain chances increase after 12Z over
much of the area with the highest chances over Orange County, the
Inland Empire, the high deserts and the San Bernardino and Riverside
County mountains 16-23Z. Isolated TSRA over mountain areas,
especially in the San Bernardino mountains, 18Z Sunday-01Z Monday.
Vis restrictions of 4-6SM and BKN-OVC CIGs at 5,000ft MSL or lower
in areas of heavier rain. Chances for rain decrease after 01Z Monday.

Deserts...Mid/high level clouds AOA 10,000-20,000ft over the south
deserts are making their way into the high deserts, and will persist
through the TAF period. VCSH will be possible in the deserts after
12z, with instances of -SHRA in the High Desert. Otherwise, VFR with
no significant impacts expected.

&&

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

&&

.BEACHES...
A large south swell from Hurricane Marie is set to peak today into
Monday before gradually diminishing Tuesday. This will result in
elevated to high surf and strong rip and longshore currents at the
majority of beaches. Additionally, waves will occasionally run much
farther up the beach than expected, especially during increasing and
high tides.

For south and southwest-facing beaches, expecting high surf 6-10
feet. This includes Orange County and north San Diego County
beaches. For west-facing beaches, expecting elevated surf 4-7 feet.
This includes most of southern San Diego County beaches.

High surf combined with high astronomical tides 6.2 to about 6.8
feet will lead to tidal overflow and coastal flooding through
Tuesday during evening high tides, especially for south and
southwest-facing beaches as well as low-lying areas.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 11 PM PDT Tuesday for Orange County
     Coastal Areas-San Diego County Coastal Areas.

     High Surf Advisory until 11 PM PDT Tuesday for Orange County
     Coastal Areas-San Diego County Coastal Areas.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE/BEACHES...Villafane

NWS San Diego (SGX) Office