083
FXUS66 KSGX 020358
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
858 PM PDT Mon Jul 1 2024

.SYNOPSIS...
Above average temperatures and hot conditions will continue through
the week for inland locations. The peak of the heat is expected to
be Friday and Saturday for most areas. Coastal low clouds will
spread into portions of the western valleys late each night and
morning this week.

&&

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

A few degrees of warming is expected for the mountains and High
Desert tomorrow, with temperatures west of the mountains and in the
low desert about the same as today. A strong ridge of low pressure
will move towards California into Wednesday, slowly moving inland
over the state this weekend. As the ridge moves into place hot
conditions are expected, with a prolonged heat wave expected in the
desert as the high very slowly moves east into the next week. By
Thursday, highs will be 5 to locally 10 degrees above average along
and west of the mountains and 10 to 12 degrees above average in the
deserts.

A shallow marine layer along the coast this week will help moderate
temperatures compared to areas further inland. Even with the marine
layer influence, above average temperatures are expected with the
hottest conditions Friday and Saturday.

From previous discussion issued at 2 PM July 1...

850 mb temperatures increase to over 30C for areas away from the
coast by Friday and Saturday, where the heat will peak in intensity
with high to extreme heat risk for inland areas away from the coast.
Highs will be near 10 to locally 15 degrees above normal, with
afternoon high temperatures well into the triple digits for the
Inland Empire and high desert. The Coachella Valley and Anza-
Borrego Desert will see very hot and near record breaking
temperatures near 120 degrees. Please limit time outdoors and drink
plenty of fluids.

This system will not only impact inland valley and desert areas, but
also coastal valley and higher elevation locations. Temperatures
will be well into the 90s into these areas on Friday and Saturday,
where Heat Advisories and Excessive Heat Warnings have been issued.
Please recreate safely and responsibly in higher terrain as
temperatures are expected to be in the low to mid 90s from Julian to
Idyllwild to Big Bear Lake. Hot weather will continue into early
next week, though the strength and location of the ridge of high
pressure becomes more uncertain per global ensembles.

&&

.AVIATION...
020400Z...Coast/Valleys...Areas of low clouds with bases 800-1300 ft
MSL and tops to 1500 ft MSL will continue to expand along the coast
through 08Z Tue and spread up to 25 miles inland by 12Z Tue. Local
VIS will be 2-4 miles in BR over higher coastal terrain and in the
coastal valleys 08Z-16Z Tue. Most areas will clear 15Z-18Z Tue with
low clouds slower to develop at the coast Tue evening.

Mountains/Deserts...Mostly clear skies with unrestricted VIS will
continue through Tue evening. Local west winds with gusts 25-35 kt
will continue through 08Z Tue on the desert slopes and through San
Gorgonio Pass. West winds will generally be weaker Tue late
afternoon/evening with most gusts 25 kt or less.

&&

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

&&

.BEACHES...
A long-period swell of 2-3 feet from 190 degrees with a period of 16-
18 seconds will arrive at SoCal beaches as early as Wednesday
morning, peak Friday and gradually subside next Sunday. This may
lead to elevated surf with breaking wave heights of 6-7 feet, mainly
on exposed south and southwest-facing beaches in Orange County. Rip
and longshore current risks will be high the second half of this
week.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning from 11 AM Friday to 8 PM PDT Saturday
     for San Bernardino and Riverside County Valleys-The Inland
     Empire.

     Heat Advisory from 11 AM Friday to 11 PM PDT Saturday for Orange
     County Inland Areas-San Diego County Valleys.

     Excessive Heat Warning from 8 AM Friday to 8 PM PDT Saturday for
     Riverside County Mountains-San Bernardino County Mountains-
     San Diego County Mountains.

     Heat Advisory from 11 AM Friday to 8 PM PDT Saturday for Santa
     Ana Mountains and Foothills.

     Excessive Heat Warning from 11 AM Tuesday to 11 PM PDT Monday
     for Apple and Lucerne Valleys.

     Excessive Heat Warning until 11 PM PDT Monday for Coachella
     Valley-San Diego County Deserts-San Gorgonio Pass Near
     Banning.

PZ...None.

&&

$$

PUBLIC...CO/APR
AVIATION/MARINE/BEACHES...Maxwell