165
FXUS66 KSGX 022053
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
153 PM PDT Tue Jul 2 2024

.SYNOPSIS...
A long-duration heat wave will continue inland through at least
the weekend. Friday and Saturday are expected to be the hottest
days for most areas with the only relief from the heat toward the
coast. The marine layer will slow the warming near the coast with
night and morning coastal low clouds spreading into the western
valleys late each night.

&&

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

Under full sunshine, temperatures near the coast are running a
little higher than yesterday at this time. It will only get warmer
in coming days and the inland heat warrants most of our attention
for the coming week. A strong upper ridge develops Wednesday just
off the coast and spills into CA and the West through Saturday.
And I do mean strong; a lot of guidance shows heights that reach
600 decameters over NorCal Thursday through Saturday. Friday and
Saturday right now appear the be the hottest days. Heat warnings
are in effect in all desert regions through next Tuesday. Heat
Warnings are in effect for mountains and inland valleys Friday and
Saturday. And Heat Advisories are in effect for inland Orange
County and the Santa Ana Mountains Friday and Saturday. This heat
wave will be significant and long-lasting even for early July.
Temps at night will not cool off much, so the accumulated heat
risk will add to the stress on humans. The marine layer will get
more shallow for the rest of the week, with less nocturnal
coverage, but coastal clouds and fog will not go away entirely.
Max temps today through Thursday will range from 2 to 12 degrees
above normal, with the greatest anomalies in the desert. On Friday
and Saturday, the hottest days, max temps will range from 6 to 15
degrees above normal. That puts Palm Springs up to 122, flirting
with the highest temps on record. The 12Z model/ensemble guidance
has a slightly better consensus on the ridge beginning to weaken
Sunday, but only slightly. Enjoy the barely noticeable drop in
temperatures of a few degrees.

&&

.AVIATION...
022000Z...Coast/Valleys...Marine layer low clouds have pulled
offshore 20-25 SM and mostly clear skies and unrestricted VIS will
continue through this afternoon. Low clouds with slightly lower
bases 600-1200 ft MSL return vcnty coastal sites 02-06Z this
evening. Vis of 3-5 SM in mist expected 09-16Z Wed over higher
coastal terrain and in coastal valleys, locally down to 1 SM. Low
clouds clearing to the coast again 15-18Z Wed.

Mountains/Deserts...Mostly clear skies with unrestricted VIS will
continue through tonight. West winds will return to the desert
slopes and through San Gorgonio Pass this afternoon/evening but will
be generally weaker, with most gusts 25 kt or less. Similar winds
Wed afternoon/evening and FEW to SCT clouds at or above 10,000 ft
MSL forming over ridgelines.

&&

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

&&

.BEACHES...
A 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 into Monday. This will lead
to elevated surf with breaking wave heights up to 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...Beach Hazards Statement from Thursday morning through Sunday
     afternoon for Orange County Coastal Areas-San Diego County
     Coastal Areas.

     Excessive Heat Warning from 11 AM Friday to 9 PM PDT Saturday
     for Riverside County Mountains-San Bernardino County
     Mountains-San Bernardino and Riverside County Valleys-The
     Inland Empire-San Diego County Mountains-San Diego County
     Valleys.

     Heat Advisory from 11 AM Friday to 9 PM PDT Saturday for Orange
     County Inland Areas-Santa Ana Mountains and Foothills.

     Excessive Heat Warning until 9 PM PDT Tuesday for Apple and
     Lucerne Valleys-Coachella Valley-San Diego County Deserts-
     San Gorgonio Pass Near Banning.

PZ...None.

&&

$$

PUBLIC...MM
AVIATION/MARINE/BEACHES...CSP