Wildfire in California, August 22 to 25, 2024

Area Forecast Discussion
National Weather Service San Diego CA
934 AM PDT Thu Aug 22 2024

.SYNOPSIS...
Dry and cooling conditions expected through Saturday. Dry conditions
are expected to continue into next week, with gradual warming Sunday
through Tuesday. The marine layer is expected to deepen into
Saturday with night and morning low clouds and fog spreading into
portions of the valleys. Monsoonal moisture could return by the
middle of next week.

&&

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

A low pressure system currently off the coast of the Pacific
Northwest will slowly move east through the weekend. This will bring
cooler conditions, a deeper marine layer, and enhance the afternoon
sea breeze. The southwesterly flow aloft will also put a pause on
any monsoon related showers and thunderstorms through at least the
middle of next week.

High temperatures today are expected to be 3 to 7 degrees cooler
than yesterday for most locations away from the low desert. High
temperatures in the lower desert will be only a couple degrees
cooler or similar to Wednesday. The cooling trend will continue into
Saturday. High temperatures are expected to be 3 to 5 degrees below
average for the coast and western valleys and low deserts. Highs in
the eastern valleys, mountains, and High Desert are expected to be 6
to 12 degrees below average. In addition to these cooler conditions,
the marine layer is expected to deepen into Saturday reaching
into the inland valleys overnight. Winds are also expected to
increase, with gusty southwesterly winds in the deserts and desert
mountain slopes with the stronger gusts in the northern Coachella
Valley below the San Gorgonio Pass to 45 to 55 mph.

As the trough of low pressure weakens and moves further inland for
early to mid-next week, that will allow for a gradual warming. The
warming trend is expected to start Sunday and continue through at
least Tuesday. By Tuesday, highs are expected to be a few degrees
above average with highs in the 90s to 103 for the Inland Empire and
105 to 110 for the lower deserts.

For the middle to end of next week, monsoonal moisture may have the
chance to return to southeastern California. NBM chances for
measurable rainfall across southwestern California will remain below
10 percent for the mountains and deserts through Tuesday. NBM
chances for thunder in the mountains does increase to around 10
percent for Wednesday afternoon of next week and 15 percent on
Thursday afternoon.

&&

.AVIATION...
221530Z...Coast/Valleys...Low clouds with bases (based near 1400ft
MSL and tops to around 1600-1700ft MSL) are quickly clearing this
morning, with SKC and VFR conditions setting in by 16-17z across the
coasts and valleys. VFR prevails throughout the day with patchy low
clouds based around 1400-1500ft MSL return as early as 03-05z this
evening, with CIGs filling into the coastal areas by 05-07z. Cloud
bases may gradually increase through the night to around 1600-1800ft
MSL, and move up to 15-20mi inland by 12-13z. Visibility reductions
to 4-5 SM possible in BR for the inland higher terrain. Clouds/fog
should clear around 16-18z Friday morning.

Mountains/Deserts...Mostly clear skies through Friday morning except
for FEW-SCT clouds around 15,000ft over the mountains from 20-02z.
Stronger west and south winds gusting to 25-35 kts from the San
Gorgonio Pass into the high desert from 20-03z may lead to moderate
updrafts/downdrafts in the lee of the mountains.

&&

.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...None.
PZ...None.

&&

PUBLIC...CO
AVIATION/MARINE...Munyan