San Diego Weather at Mission Trails, CA

000
FXUS66 KSGX 012044
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
144 PM PDT Sun Oct 1 2023

.SYNOPSIS...
A low pressure system will bring another unseasonably cool day
today with isolated to scattered showers ending tonight. Dry and
warmer weather will begin Monday as the low pressure weakens and
lifts north. High pressure and increased offshore flow will boost
the warming trend for above average temperatures Wednesday through
Saturday.

&&

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

Shower activity continues this afternoon, but has decreased a bit
from this morning. Off and on showers will occur through this
evening, then diminish overnight.

Clouds have started clearing out a bit this afternoon, especially
along the coast. Further clearing will continue through tonight as
the low lifts north. The marine layer will struggle to redevelop
tonight as the low lifts out, so low cloud coverage will be
patchy at best tonight.

It will continue to be cool today, with high temperatures 5 to 10
degrees below average at the coast and 15 to 25 degrees below
average inland. Winds have overall decreased from yesterday,
though some gusts to 45 mph will remain through the passes through
tonight.

High pressure will begin to build over the West Coast on Tuesday,
with a remnant low sticking around over Arizona for much of the
next week. This will set us up into an offshore pressure gradient,
with resultant Santa Ana winds over the mountains and valley
foothills. The winds will start out quite weak on Tuesday, then
strengthen for Wednesday and Thursday. The exact strength of the
winds remains uncertain at this time, but it is currently looking
to be a weak Santa Ana wind event.

As these winds push over the foothills of the valleys, the airmass
will warm up and the offshore flow will greatly increase
temperatures west of the mountains. High temperatures today will
be well below average, by Tuesday we will approach average, then
well above average for the end of the week. Temperatures in the
valleys and inland coastal areas will reach well into the 90s,
and even the immediate coast will get into the 80s Wednesday
through Saturday. This is about 10 to 15 degrees above average
for those areas. With the stronger offshore winds, warmer
temperatures, and lower humidity, we could see some brief elevated
fire weather conditions for late next week.

There remains differences in the ensembles on when the offshore
flow will weaken, but it appears to weaken at some point next
weekend, which would ease temperatures back closer to average.

&&

.AVIATION...
012035Z...Coast/Valleys...Isolated to sct -SHRA through 06Z tonight.
then becoming SKC/SCT thereafter. Bases will be mainly variable and
between 3000-5000 ft MSL, layered to 7000 ft MSL...but clouds should
lower to 2500-3500 feet MSL with tops around 5000 feet MSL and
mainly sct by midday Monday morning.

Mountains/Deserts...Areas of mountain obscuration in clouds and
-SHRA through 06Z tonight. Decreasing cloud cover tonight. Areas of
W-SW winds gusting 25-40 knots on the mountain crests and the desert
slopes east of San Gorgonio Pass decreasing overnight.

&&

.MARINE...
No hazardous marine conditions through Thursday.

&&

.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...Connolly
AVIATION/MARINE...Small