San Diego Forecast Discussion

000
FXUS66 KSGX 020409
AFDSGX

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

.SYNOPSIS...
Our cold storm system will be exiting the region on Monday, setting
up a warming trend that will continue all week. A few more sprinkles
will occur overnight, but most areas will stay dry. Fair and much
warmer weather is on the way after Monday, culminating in
temperatures will above average Thursday through Saturday.

&&

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

Through 9 PM PDT...Radar still was detecting a few, isolated, light
showers, but gage accumulation had mostly ended.  Isolated, light
showers may continue through the night, but most areas will stay
dry. The 00Z Miramar sounding continues to show cooling in the
profile, and drying too, but some stabilization has occurred.
Westerly wind gusts were mostly under 25 MPH now, but there were
still a few gusts around 40 MPH in the San Gorgonio Pass. Look for
fair and warmer weather on Monday, with the warming accelerating
through midweek. No forecast updates are planned.

From previous discussion...

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...
020345Z...Coast/Valleys...Areas of low clouds with bases mostly 3000-
5000 ft MSL, layered to 9000 ft MSL obscuring higher terrain inland
through about 15Z. SCT to locally BKN CIGS 2000-2500 ft MSL at times
through 15Z with low confidence for impacts at TAF sites. Mostly
clear after 15Z.

Mountains/Deserts...Decreasing cloud cover along the coastal mtn
slopes tonight. Areas of W-SW winds gusting 25-40 knots on the
mountain crests and the desert slopes east of San Gorgonio Pass
weakening 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...10
AVIATION/MARINE...PG

NWS SGX Office Area Forecast Discussion