Rancho California California Weather Forecast Discussion

065
FXUS66 KSGX 100421
AFDSGX
Area Forecast Discussion
National Weather Service San Diego CA
921 PM PDT Thu Oct 9 2025
.SYNOPSIS...
A low pressure system off the West Coast will draw moisture from
Tropical Cyclone Priscilla northward into the area through Saturday
morning, with chances for showers and thunderstorms at times. Cooler
with drying and a return of the marine layer early next week. For
Tuesday and Wednesday of next week, a low pressure system moving
southward along the West Coast will bring a chance of showers along
with stronger westerly winds.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
Areas of rain were present for much of the afternoon. A rainfall
total summary has been headlined on our weather.gov/sandiego
homepage. At 9 PM a band of showers was moving from south to
northeast across San Diego County, with some isolated light showers
elsewhere. Radar and rain gauges are indicating rainfall is mostly
light, with pockets of locally moderate rain. Areas of rain will
become more isolated overnight, with showers and thunderstorms still
expected to develop Friday afternoon and evening in the mountains
and deserts.
From previous discussion issued at 2 PM October 9...
Through tonight, the moisture plume will continue to move up from
the south and over the region, with likely a mid level cloud shield
and intermittent showers, for even the coastal and inland areas
overnight. By tomorrow, the area of low pressure associated with
this weakening tropical system will become absorbed into the
trough to our south and increasing southerly flow with more
instability will give way to a better chance of showers and
thunderstorms for tomorrow, especially over the mountains and
deserts. An isolated storm over the mountains can`t be ruled out
during the afternoon on Saturday, otherwise conditions will become
much drier and cooler.
The rest of the weekend though the end of next week...
The forecast still appear to be on track with the system becoming
sheered off towards the east by early Saturday morning, with chances
of precipitation diminishing as it does and a temporary drying trend
on Sunday. With much more influence from the trough upstream, and
the will carry into next week, as a series of deepening troughs
bring bouts of light rain and cooler temperatures to southern
California. Some of the deterministic models are also hinting at a
possible impactful area of low pressure which could potentially
given portions of the region very beneficial amounts during the mid
part of next week. Temperatures could get much colder, and there
could even be some of the higher elevations getting measurable snow
for the first time of this year`s rainy season.
&&
.AVIATION...
100300Z....BKN high clouds based 6,000-10,000 feet MSL with
Scattered -SHRA and isolated TSRA through the TAF period. Greatest
chances for TSRA in the afternoons/evenings over mountains and
deserts. VCSH placed in TAFs to cover uncertainty in timing for
showers over sites with -SHRA included for areas with higher
confidence in timing. Any TSRA could lower cloud bases to 4000 feet
MSL briefly, and could bring gusty winds and reduced vis in +RA.
Chances for SHRA will move away from coastal sites by 00Z.
&&
.MARINE...
Northwest winds occasionally exceeding 20 knots around San Clemente
Island during the afternoons and evenings Friday and Saturday. Rain
and thunderstorms are expected to stay close to the coast Friday
afternoon.
&&
.BEACHES...
There is a 5-15% chance of thunderstorms producing lightning
Friday, most likely during the afternoons.
&&
.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 UPDATE...CO
PUBLIC PREVIOUS DISCUSSION... Stewey
AVIATION/MARINE/BEACHES...Villafane

NWS SGX Office Area Forecast Discussion