352
FXUS66 KSGX 252140
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
140 PM PST Tue Nov 25 2025

.SYNOPSIS...
Offshore flow through Thursday will keep things dry and temperatures
well above normal. Periods of gusty east winds exceeding 25 mph at
times in the mountains and through passes tonight into Wednesday.
The next weather system arrives this weekend with cooler weather and
a chance for light rain or rain/snow on Sunday. As the system moves
out on Monday, a warming and drying trend sets up with another round
of offshore flow for early next week.

&&

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

Quieter weather the next several days with a ridge building overhead
and weak Santa Ana winds ushering in above-normal temperatures and
low humidity. Gusts around 25-30 mph have already been observed
along the western slopes of the mountains and through passes today,
with periods of increasing winds tonight into Wednesday possible. As
these winds push in dry and warm air, humidity will fall to the low
teens for the Inland Empire and neighboring valleys/inland areas
Wednesday afternoon, while temperatures will climb to the 80s for
most locations outside of the mountains and those directly along the
coastline. Wednesday will be the peak of the heat, around 6 to 13
degrees above normal for the end of November. Heading into the end
of the week, a shortwave embedded in the larger pattern will move
eastward, breaking down the ridge a bit and setting up more zonal
flow aloft. With this shift, the Santa Ana winds will weaken and
clouds will increase, lowering temperatures a bit on Thursday and
allowing the possibility of a very patchy marine layer to
redevelop. This will begin our transition to cooler weather with
highs a few degrees less each day, better moisture recovery
overnight, and a deepening marine layer into Saturday.

The next system is set to arrive this weekend as a deepening inside
slider, with cooler temperatures aloft and a slight uptick in
precipitation chances region-wide. At this point, moisture looks
somewhat limited with this next system, and some global models are a
bit hesitant to jump on the rain chances at all. Current
forecasted QPF/liquid equivalent with this next system is very
low, generally less than 0.05-0.15" in a 24 hour period Sunday
into Monday for the coasts and valleys, and 0.15-0.40" in a 24
hour period for the mountains. There is only about a 20% chance
for 24 hour precipitation exceeding 0.25" for San Diego, 25%
chance for 24 precipitation exceeding 0.25" for Big Bear, and 13%
for Palm Springs. Regardless of how the precipitation pans out,
one of the more impactful features of this system may be the snow
levels, poised to fall from around 7000ft on Saturday to
5500-6000ft early Monday morning, possibly lower. Even with
limited moisture, any showers that develop may include some
snowflakes and even light accumulations for elevations above 5000
into Monday. Outside of the rain/snow chances, the position of
this trough will help flip surface winds north/northeasterly
Monday into Tuesday, with drier and warmer weather setting in
through the middle of next week.

&&

.AVIATION...
252030Z...Coasts...VFR very likely through the period, with less
than 20% chance for CIGs this evening (highest chances after 26/05Z
through 26/12Z).

Valleys/Mountains/Deserts...VFR conditions expected through tonight.
E to NE winds locally gusting 25-35 kts along coastal slopes of the
mtns will expand to include adjacent foothills and portions of the
Inland Empire after 18Z. Areas of LLWS/low-level turbulence along
foothills/west mtn slopes.

&&

.MARINE...
No hazardous marine conditions are expected through most of
Saturday. There is the potential for elevated winds and seas towards
late Saturday or Sunday with an approaching storm system, but the
forecast remains uncertain at this point; stay tuned for updates.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.

&&

$$

PUBLIC...Zuber
AVIATION/MARINE...Small