172
FXUS66 KSGX 281614
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
914 AM PDT Fri Jun 28 2024

.SYNOPSIS...
Hot weather will increase inland this weekend while coastal low
clouds will be less extensive. The heat will be excessive in the
lower deserts Sunday and Monday. It will continue very hot inland
for the entire coming week, especially in the deserts. The
shallower marine layer will modify temperatures near the coast.

&&

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

The marine layer brought coastal low clouds as far as the
southern Inland Empire this morning, assisted by a weak coastal
eddy. The eddy will go away today and low clouds have already
cleared from most land areas by 9 am. High pressure aloft will
dominate the weather picture over the West for the foreseeable
future. This will mean very hot weather in the deserts and to a
lesser extent in the inland valleys. A weak trough to our
northwest and a big ridge to our east will jockey for position
over SoCal this entire coming week. The ridge will gain the upper
hand, and bring the hot weather. An Excessive Heat Watch is in
effect for Sunday and Monday in the lower deserts, where temps
will rise to 116 or so. But this Watch, and eventual Warning, may
need to be extended. Only a couple degrees of "cooling" can be
expected Tuesday through Thursday, but good agreement in models
and ensembles are showing another, more significant, high pressure
ridge toward next weekend. Right now it appears temps next weekend
will exceed temps this weekend. We`ll probably break some
records, too. Meanwhile, back at the coast, the marine layer will
get squashed and disrupted by the higher pressure aloft, so low
clouds will become lest extensive and less uniform in coverage.
Temperatures inland appear 4-10 degrees above average on Sunday,
the hottest day through next Friday. But get ready for even
hotter inland weather the following weekend.

&&

.AVIATION...
281600Z...Coast/Valleys...Some lingering low clouds with bases
1300-1900 feet and tops to 2050 feet MSL along beaches and
southwest San Diego Co., but otherwise the marine layer has pulled
west out of inland regions. Clearing will continue through 18Z.
Low clouds returning to VCNTY coastal TAF sites 03Z-06Z Sat,
pushing inland to similar extent as last night, and retreating
back to beaches again 16-18Z.

Mountains/Deserts...SCT clouds at or abv 10,000 ft MSL this
afternoon. Otherwise mostly clear with unrestricted VIS through
this evening.

Northwest winds gusting to 45 mph in the wind-prone passes and
canyons again this afternoon with moderate up/downdrafts over and
east of the mtns.

&&

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

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Watch from Sunday morning through Monday evening
     for Coachella Valley-San Diego County Deserts-San Gorgonio
     Pass Near Banning.

PZ...None.

&&

$$

PUBLIC...MM
AVIATION/MARINE...Small/CSP