126
FXUS66 KSGX 271605
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
905 AM PDT Thu Jun 27 2024

.SYNOPSIS...
Drier and slightly cooler inland for Friday and Friday night.
Warming is expected for Saturday and Sunday with Sunday highs
around 5 to 10 degrees above average, to around 115 for the lower
deserts and around 100 for the far inland valleys. Night and
morning coastal low clouds will continue to extend inland into
portions of the valleys late each night. There may be slight
cooling into the middle of next week with renewed warming toward
the end of next week if strong high pressure aloft develops across
California and Nevada.

&&

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

.Morning Update...

Low clouds are beginning to clear near the coast this morning
after blanketing much of the western valleys earlier. The ridge
that has been providing monsoonal conditions over the Southwest
has slowly began to weaken today, which as led to some drier air
to infiltrate our region. Precipitable water values have lowered
near 1.50" this morning, a bit drier than yesterday. This will
shift monsoon storm chances eastward out of the area today, where
minimal chances of rain are now expected into at least early next
week.

Temperatures will be fairly similar over the next few days with
warmer conditions expected by Sunday into early next week as high
pressure regains control of the overall weather pattern. The
marine layer will be slightly deeper the next couple of nights,
where low clouds may reach locally into the Inland Empire. Clouds
will stay near the coast and adjacent valleys as the marine layer
becomes shallower.

.Previous Discussion (303 AM Thursday)...

.SHORT TERM (Today through Saturday)...
High temperatures for the coast and valleys will warm a few to
around 5 degrees today with not much change elsewhere. Little
change for Friday, then high temperatures for Saturday will warm a
few to around 5 degrees with the greatest warming in the valleys.

After setting a record for the highest precipitable water value
for June for San Diego of 1.78 inch early Wednesday, developing
southwest flow aloft will bring a drying trend into early Saturday
with precipitable water values falling to around 0.70 inch.
That`s a little below the climatological average for late June.
NBM has surface dewpoints at Palm Springs falling from around 60
early this morning to around 36 on noon Saturday.

Low clouds along the coast of Baja extend northward along the
coast of San Diego and Orange Counties into southern Los Angeles
County. The low clouds extend locally inland along the coast and
into portions of the western valleys in San Diego. The low clouds
are expected to extend a little farther into the valleys for
tonight into Friday morning.

&&

.LONG TERM (Sunday through Wednesday)...
Warming will continue into Sunday with Sunday high temperatures
generally 5 to 10 degrees above average, to around 115 in the
lower deserts and around 100 for portions of the inland valleys.
NBM has dewpoints for Palm Springs increasing into the 40s on
Sunday and into the 50s by Wednesday with overnight low
temperatures mostly in the 80s for Palm Springs beginning on
Sunday. Toward the end of next week, strong high pressure aloft
could be centered somewhere across California and Nevada which
could bring some of the hottest weather so far this summer for
inland areas by Friday and Saturday of next week.


&&

.AVIATION...
270840Z...Coast/Valleys...Low clouds with bases 1300-1800 ft MSL and
tops to 2100 ft MSL are swiftly retreating west towards the coast.
Clearing continuing through 18-19Z for coastal sites. Clouds
redeveloping near the coast 28/00-03Z and spreading 15-20 mi inland
again tonight into Fri morning with similar bases/tops. Otherwise
mostly clear with unrestricted vis through Fri morning.

Mountains/Deserts...West winds with sfc gusts 25-35 kt developing
across portions of the mountains and deserts around 20Z. Local gusts
to 45 kt through the San Gorgonio Pass. Mod up/downdrafts over and
east of the mountains. Winds diminishing early Friday morning.
Otherwise a few Cu developing over the mountain crests this
afternoon, dissipating by sunset, and unrestricted vis.

&&

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

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning until 8 PM PDT this evening for Coachella
     Valley-San Diego County Deserts-San Gorgonio Pass Near
     Banning.

PZ...None.

&&

$$

PUBLIC...APR/17
AVIATION/MARINE...CSP