787
FXUS66 KSGX 080957
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
257 AM PDT Tue Jul 8 2025

.SYNOPSIS...
Warmer for Wednesday and Thursday with high temperatures 5 to 10
degrees above average for inland areas. Not quite as hot for
Friday through early next week with the coast and valleys near to
around 5 degrees below average with the deserts around 5 degrees
above average. Night and morning coastal low clouds will spread
into portions of the western valleys late each night.

&&

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

.SHORT TERM (Today through Thursday)...
A low pressure system off the northern California coast will
weaken and move inland while high pressure aloft centered over
Arizona and New Mexico expands across southern California. This
will bring warming for today and Wednesday with not much change
for Thursday.

High temperatures on Wednesday and Thursday will be a few degrees
above average near the coast to around 10 degrees above average
for the deserts. High temperatures on Wednesday and Thursday will
range from the 70s near the coast to the mid 90s to 104 for the
Inland Empire with 114 to 118 for the lower deserts.

The marine layer will decrease in depth to around 1500 feet deep
for Wednesday and Thursday with night and morning coastal low
clouds spreading into portions of the western valleys late each
night.

&&

.LONG TERM (Friday through Monday)...
On Friday, high pressure aloft will weaken slightly and onshore
flow will strengthen slightly with the coast and valleys around 5
degrees cooler than Thursday with the deserts a few degrees cooler
with not much change for the weekend into early next week.

High temperatures will be near to around 5 degrees below average
for the coast and valleys with the deserts around 5 degrees above
average. High temperature will range from the lower to mid 70s
near the coast to the upper 80s to upper 90s for the Inland
Empire with 110 to 114 for the lower deserts.

Night and morning coastal low clouds will spread inland into the
western valleys late each night.

&&

.AVIATION...
080900Z....Coast...Very patchy low clouds based 1200-1500 ft MSL are
up to 10 miles inland in SD County. High uncertainty whether CIGs
impact KSNA and Orange County broadly (about a 40% chance), with
timeframe between 09-14z. vis reduced to 1-5SM in BR along inland
and higher elevation coastal areas. Scatter out Tuesday 14-16Z.
Increasing upper level clouds above 12000 ft Tuesday. Even patchier
low clouds with slightly lower bases to form after 06Z Wed.

Valleys/Mountains/Deserts...Unrestricted VIS through Wednesday with
increasing mid/high cloud coverage this morning.

&&

.MARINE...
NW wind gusts around 20 kts near San Clemente Island Tuesday and
Wednesday in the afternoons and evenings. Otherwise, no hazardous
marine weather is expected through Saturday.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory from 10 AM Wednesday to 8 PM PDT Thursday for
     Riverside County Mountains-San Bernardino and Riverside
     County Valleys-The Inland Empire-San Diego County Mountains-
     San Diego County Valleys.

     Extreme Heat Warning from 10 AM Wednesday to 8 PM PDT Thursday
     for Coachella Valley-San Diego County Deserts.

PZ...None.

&&

$$

PUBLIC...17
AVIATION/MARINE...Westerink