741
FXUS66 KSGX 221628
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
928 AM PDT Wed Oct 22 2025

.SYNOPSIS...
Cooler weather today despite a patchy marine layer this morning,
with gusty winds on the eastern slopes of the mountains this
afternoon and evening. A deeper marine layer tongiht backing up
to the coastal slopes of the mountains with areas of low
visibility for Thursday morning. A warming and drying trend
Thursday and Friday with highs returning to near normal before
cooler and windier weather returns for the weekend. Warmer
temperatures closer to normal for Monday-Wednesday.

&&

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

.UPDATE...
After a few light showers this morning, precipitation has ended
region-wide. Gusty west winds exceeding 30 mph have already
occurred in the Banning Pass, with gusts up to 50 mph expected
this afternoon and evening across the desert slopes and mountain
passes. Patchy low clouds are lingering across the coasts and
valleys this morning, which should continue to clear into the
afternoon. A deeper marine layer is expected for Thursday morning,
which will back up to the coastal mountain slopes with low
visibilities at times early Thursday. Otherwise, drier and warmer
temperatures Thursday and Friday, returning back to near normal.
The next system set to arrive this weekend will bring cooler
temperatures and strong winds for much of SoCal, although any
precipitation will remain too far north for us to benefit from. As
this system moves out Monday, more zonal flow aloft will bring us
back to near normal to slightly above normal temperatures into
the middle of the week.

.PREVIOUS FORECAST FROM 340 AM PDT...
.SHORT TERM (Today through Friday)...
A low pressure system centered just west of Point Conception early
this morning will move inland through central and southern
California today into this evening. The elevated convection to
the north and east of the low pressure center will move east of
the area this morning.

This convection has produced some lightning and little rainfall,
mostly across portions of San Bernardino and Riverside Counties
with any measurable rainfall a few hundredths of an inch. The
marine layer has deepened to around 2500 feet and will continue to
deepen tonight to around 4000 to 4500 feet with night and morning
coastal low clouds extending inland across of the valleys and
onto the lower coastal slopes of the mountains for tonight into
early Thursday morning.

Today will be much cooler for inland areas with high temperatures
for the mountains and inland valleys as much as 12 to 18 degrees
cooler than Tuesday. High temperatures for today will be as much
as 5 to 10 degrees below average for the mountains and valleys
with high temperatures ranging from the upper 60s near the coast
to the lower to mid 70s for the Inland Empire with the 80s for the
lower deserts. Southwest winds will gust to 35 to 45 mph along and
below the east slopes of the mountains for this afternoon and
evening.

There will be warming with weaker winds for Thursday and Friday
with Friday high temperatures around 5 degrees above average
for inland areas, ranging from the lower to mid 70s near the coast
to the mid to upper 80s for the Inland Empire with the lower to
mid 90s for the lower deserts.

.LONG TERM (Saturday through Tuesday)...
A low pressure system to the north will strengthen the onshore
flow across southern California for the weekend. This will deepen
the marine layer with coastal low clouds spreading into portions
of the inland valleys by Sunday with periods of gusty southwest to
west winds for the mountains and deserts. There will be cooling
for Saturday and Sunday with Sunday high temperatures mostly a few
to around 5 degrees below average, ranging from around 70 near the
coast to the mid to upper 70s for the Inland Empire with the mid
to upper 80s for the lower deserts.

Monday and Tuesday will be dry with warming with Tuesday high
temperatures slightly below average for the mountains and deserts
and as much as 4 to 8 degrees above average for the western
valleys and inland coastal areas. High temperatures on Tuesday
will range from the 70s near the coast to the 80s for the valleys
with the mid to upper 80s for the lower deserts. There could be
weak offshore flow for Tuesday and Wednesday with locally gusty
northeast to east winds along and below the coastal slopes of the
mountains.

&&

.AVIATION...221530Z...Coast/Valleys...Patchy low clouds based 1500-
2000 ft MSL will result in intermittent CIGs through about 17Z this
morning followed by clearing low clouds. Patchy low clouds 2000-3000
ft MSL will form in San Diego Co after 00Z, gradually covering most
of the coastal basin into foothills by early Thursday. These will
scatter out from most inland areas 13-16Z but linger along the coast
through about Thu 18Z.

Mountains/Deserts...Westerly winds will strengthen this morning with
strongest gusts 35-45 kts through mountain passes and on desert
slopes. Strong up/downdrafts and local LLWS in lee of mountains,
such as vcnty KPSP.

&&

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

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from noon today to midnight PDT tonight for San
     Diego County Deserts-San Gorgonio Pass near Banning.

PZ...None.

&&

$$

PUBLIC...Zuber
AVIATION/MARINE...CSP

NWS Tucson (SGX) Office