404
FXUS66 KSGX 060404
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
904 PM PDT Sat Jul 5 2025

.SYNOPSIS...
High temperatures near average with night and morning low clouds
closer to the coast can be expected through Monday. High pressure
over the Desert Southwest will build into the region for Tuesday
into later next week, bringing hotter weather for inland areas.

&&

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

This evening, the marine layer is about as deep as this time
yesterday but may deepen a little overnight as heights aloft fall.
Low clouds are beginning to form along the coast at this hour and
high-resolution models indicate that low clouds and fog will
spread up to about 10 miles inland before sunrise. Patches of fog
on elevated coastal terrain could be locally dense later tonight
into Sunday morning.

From previous discussion...
An upper level low near the Bay Area is helping to keep our
temperatures near average for early July. Foggy conditions will
occur in coastal valleys and elevated terrain each morning through
Monday. High temperatures will not change much either by Sunday
and Monday with readings near average.

Models continue to indicate the area of high pressure to our
south and east will strengthen over the Dessert Southwest. By
Tuesday, this will increase temperatures a few more degrees than
what we are currently experiencing this weekend. Ensemble models
show the area of high pressure peaking over the region on
Wednesday through at least Friday, prompting the first notable
heat wave of the summer. Low level monsoonal moisture will begin
to move into the region by Tuesday and Wednesday. There continues
to be a near zero chance of thunderstorm activity, with some
cumulus clouds possible over mountain peaks. This increasing
humidity will make the hot weather feel a bit more oppressive,
especially across the lower deserts. Humidity will decrease
slightly into the end of the week. For anyone living in valleys
west of the mountains and desert regions, please stay safe in the
heat if you are without any sufficient cooling measures or have to
work outside during this time into the end of next week. High
temperatures will be in the mid 80s to mid 90s across the
mountains as well, so any outdoor recreation should be limited to
early morning or evening hours to avoid the hottest part of the
day.

The warmest weather will take place by Wednesday and Thursday
with high temperatures increasing to 5 to 10 degrees above normal.
Chances for 100 degree or greater temperatures are high across
the IE and the high desert, with confidence increasing across
portions of the Inland Empire. This is closer to 40-70% for inland
valleys/foothills across San Diego County such as Ramona and Pine
Valley. Highs over 115 across the lower deserts still remains
somewhat in question as higher humidity can act to suppress the
the hot dry air that is typically associated with high pressure
systems of this magnitude. Confidence is increasing that only
subtle cooling will occur into later next week, keeping things
above average and warm.

&&

.AVIATION...
060330Z....Coast/Valleys...Patchy low clouds based 700-1200 ft MSL
have begun to form offshore and will move onshore late tonight,
likely after 06Z. Clouds will move 10-15 miles inland, bringing vis
reductions 2-4 SM to elevated coastal terrain and western valleys.
Clouds clear 15-17Z Sun. Low clouds 900-1400 ft MSL reform and move
ashore again after 04Z Mon.

Mountains/Deserts...Mostly clear with unrestricted VIS through Sunday.

&&

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

&&

.BEACHES...
Southerly swell (190 degrees) of 3 to 4 feet at 14-16 seconds will
generate elevated surf of 4-6 ft with sets to 7 ft along south
facing beaches through Sunday. In addition, strong rip and longshore
currents are expected at all beaches through Sunday. A Beach Hazards
Statement is in effect and contains more information. Surf may
remain elevated into early next week.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Sunday evening for Orange County
     Coastal Areas-San Diego County Coastal Areas.

PZ...None.

&&

$$

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