629
FXUS66 KSGX 180539
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
1039 PM PDT Fri Jul 17 2026

.SYNOPSIS...
Temperatures cooling for inland areas today will be similar into
much of next week. Chances of thunderstorms are elevated once
again across the mountains this afternoon. Storm chances begin to
decrease with minor chances expected for highest ridges in the San
Bernardino and Riverside County mountains each afternoon into the
first half of next week. Confidence lowers for increasing chances
later in the week. Low clouds will continue to cover coastal
areas each night and morning into the next week as well.

&&

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

...UPDATED AVIATION DISCUSSION...

...UPDATED BEACHES DISCUSSION...

PREVIOUS DISCUSSION...1245 PM PDT Fri Jul 17 2026...
Satellite imagery shoes shows mid-level clouds over parts of
SoCal and further to the east, with drying trends noticed over
northern portions of the mountains. Clearing this morning will
create a better environment for thunderstorm activity as we head
into the afternoon. Comparing yesterday to today, the environment
is seemingly a bit less primed with less instability, though PWATs
are still near 1.5", plenty moist enough. Latest hi- res model
guidance again favors the Riverside and San Diego County mountains
to receive the greatest rainfall, locally near 0.50"-1" per hour
rates, for later this afternoon. Storms will begin to weaken by
early evening. Otherwise, temperatures today will feel not as hot
as yesterday. High temperatures will be closer to average with
highs in the 90s across the IE and high desert, and 70s/80s for
the coast, western valleys and mountains. Elevated humidity with
overnight lows near to slightly above average will remain though.

Moisture around an area of high pressure over the Intermountain West
decreases and pushes further east by the weekend. Moisture will
still remain in place, so chances do remain over the higher
mountains of SBD/RIV Counties on Saturday. The atmosphere looks to
dry out a bit further by Sunday through Tuesday, bringing chances
near 10-15% along the eastern parts of the SBD Mts. Other than this,
the overall weather pattern will remain relatively unchanged with
temperatures near average with mostly clear conditions.

The forecast in monsoonal moisture becomes less certain by the
latter half of next week. Models still continue to be split on the
placement of the area of high pressure, which will dictate where and
how much monsoonal moisture we are able to receive. This will also
dictate if we stay near normal or warm slightly above normal.

&&

.AVIATION...
180530Z....Coast/Valleys...Mid-level clouds 15-20kft MSL are
currently inhibiting low clouds from forming along the coast, which
will likely continue through 08-09Z. Patchy low clouds 900-1300 ft
MSL will move into coastal regions after, becoming more widespread
as mid-levels continue to clear towards around 12Z. Low clouds clear
15-17Z, then reform at similar bases and move into coastal regions
after 05Z Sun.

.Mountains/Deserts...VFR conditions expected through the period with
SCT mid-level clouds AOA 15,000ft MSL gradually clearing overnight.
SCT Cu based 10-12 kft MSL will develop over the Riverside and San
Bernardino mtns after 18Z and ISO-SCT SHRA/TSRA , most likely after
20Z, through 01Z Sunday. Any storms that develop may produce
lightning, gusty winds, and vis reductions.

&&

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

&&

.BEACHES...
High amplitude southerly swell (4-5 ft with a period of 12-13
seconds) will build Sunday, bringing elevated to high surf and
strong rip and longshore currents for Sunday through at least
Tuesday. Highest surf, up to 7-9 ft, will be along south and
southwest-facing beaches. Further details can be found in the High
Surf Advisory. Surf falls a bit after Tuesday and into Wednesday
before another stronger southerly swell (3-4 ft with a period of 15
seconds) brings another round of elevated surf for the end of the
week and into the early weekend. The high risk for strong rip
currents will remain from Sunday through next week.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...High Surf Advisory from 5 PM Sunday to 11 PM PDT Tuesday for
     Orange County Coastal Areas-San Diego County Coastal Areas.

PZ...None.

&&

$$

PUBLIC...PG
AVIATION/MARINE/BEACHES...CSP