178
FXUS66 KSGX 141639
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
939 AM PDT Fri Jun 14 2024

.SYNOPSIS...
Above average temperatures are expected for inland areas today and
Friday. Several degrees of cooling is expected for Sunday and
Monday, before another round of more gradual warming for Tuesday
through Friday. Night and morning low clouds will continue along
the coast, spreading into portions of the valleys at times. There
will be stronger and gusty southwest to west winds for the
mountains and deserts for this weekend during the late afternoon
through late evening each day. Daytime relative humidity will fall
to 10 to 15 percent in the same areas impacted by wind, creating
elevated fire weather conditions.

&&

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

Low clouds have been rapidly clearing to the coast this morning with
some beaches in San Diego seeing sunshine. With increasing high
pressure aloft, low cloud and fog coverage will become more
confined to the coast, potentially reaching into portions of the
far western valleys tonight into Saturday morning. Areas of
patchy fog are possible tonight into early Saturday morning,
especially near mesas and other higher coastal terrain. The marine
layer is expected to begin to deepen again Sunday and Monday,
with higher chances of reaching further into the valleys during
that time.

High temperatures today are expected to be a few degrees warmer than
yesterday at the coast with 5 to 12 degrees of warming for inland
areas. An additional few degrees of warming is expected for inland
areas tomorrow, with 3 to 7 degrees of warming for coastal areas.
High temperatures for the hottest locations in the lower deserts
around 115 and in the Inland Empire around 100. Areas of moderate to
locally major heat risk are expected for the low deserts today and
Saturday with moderate heat risk in the Inland Empire Saturday.
With these hot conditions it`s recommended to avoid strenuous
outdoor activities if you can, especially between the hours of 10
am and 5 pm, and stay hydrated.

Sunday will be noticeably cooler across the area as a broad
troughing pattern holds over the Western United States. Widespread
cooler conditions will maintain into Monday. In addition to cooler
conditions and increased low cloud coverage, the increase in onshore
flow will generate gusty southwest to west winds for the mountains
and deserts each late afternoon through late evening for the weekend
with gusts to 30 to 40 mph with isolated gusts to around 50 mph in
the northern Coachella Valley below the San Gorgonio Pass.

By Tuesday, guidance is indicating gradual warming will begin for
areas in and west of the mountains. That warming is expected to spread
to the deserts by Wednesday with continued warming for all areas into
at least next Friday. By next Thursday, there is over 60% chance
that above average temperatures will return to the lower deserts,
with chances increasing to over 90% for next weekend. This is a
good indicator that summer is finally settling in, with the
potential for a longer duration heat wave for next weekend into
the following week (week of June 23).

&&

.AVIATION...
141600Z...Coast/Valleys...Rapid clearing this morning across San
Diego county coast. This will expand into Orange County through 17z.
Less marine layer is forecast Friday night and Saturday and more
confined to the immediate coast as upper ridge warming builds
overhead in the wake of the upper trough exiting Arizona. Chances
for low cloud formation is 60 percent for Saturday morning at KCRQ
and KSAN, and 30 percent for KSAN and ceilings will be lower near
1000 feet and 30 percent chance of IFR ceilings and MVFR visibility.


Mountains/Deserts...SKC with unrestricted VIS. Gusty W-NW winds
picking up after 20z Fri, with peak surface wind gusts of 25-35
knots expected. MOD UDDFS expected over and east of the mountains.

&&

.MARINE...
Northwest winds may gust to around 20 knots at times in the far
outer waters near San Clemente Island each afternoon and evening
Saturday through Monday. No other hazardous marine conditions
expected.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory from noon to 8 PM PDT Saturday for San Bernardino
     and Riverside County Valleys-The Inland Empire.

     Excessive Heat Warning until 8 PM PDT Saturday for Coachella
     Valley-San Diego County Deserts-San Gorgonio Pass Near
     Banning.

PZ...None.

&&

$$

PUBLIC...CO
AVIATION/MARINE...Tardy