Swell Matrix

Area Forecast Discussion

National Weather Service San Diego CA

453 am PST Tue Nov 18 2025

Synopsis

Widely scattered, mostly light showers will continue today into this evening with the next Pacific low pressure system from the northwest bringing another round of more widespread showers for Thursday night and Friday with decreasing chances for showers into next weekend. Drier and warmer for next week.

Discussion

For extreme southwestern California including Orange, San Diego, western Riverside and southwestern San Bernardino counties,

Short Term

(today through Thursday), A closed upper level low pressure system is centered near Point Conception early this morning. The center of this low pressure system will move to near San Diego early Wednesday, then near the Colorado River by late Wednesday afternoon. The back edge for the precipitation with the cold front is near the mountains of Riverside and San Diego Counties and will continue to move slowly eastward early this morning. Rainfall since Monday for Orange and southwestern San Bernardino Counties has mostly been one-quarter to one-half inch for the Orange County coastal plain for the Inland Empire with around one inch in the mountains. For San Diego County, rainfall for the coast and valleys has been one-half to locally more than one inch with one-qaurter inch or less for the mountains in central and southern San Diego County.

Widely scattered mostly light showers will continue today, possibly continuing into this evening for the coastal waters with additional rainfall of one-quarter inch or less. The snow level has lowered to around 6500 feet and will continue to lower today to around 5500 feet with additional snowfall today of a few inches, mostly above 6000 feet.

Wednesday will be drier and slightly warmer, though with a continuing slight chance of showers for the mountains. The next low pressure system from the northwest could bring some light showers as early as late Thursday morning or Thursday afternoon with the more widespread showers arriving on Thursday night. A snow level near 5500 to 6000 feet early Thursday morning will rise to around 6500 to 7000 feet by late Thursday afternoon.

Long Term

(Thursday through Monday), The more widespread showers are expected to arrive on Thursday night and continue into Friday. Showers should begin to decrease on Friday night, but there's greater model spread on just how far into the weekend that some showers might linger with the chance of measurable precipitation in the mountains decreasing to around 30 percent on Saturday and 15 percent on Sunday. For early Thursday morning through late Friday night, the chance of one inch or more of liquid equivalent for the mountains is 50 to 60 percent with a 30 to 40 percent chance for two inches or more in the mountains. The snow level will be mostly 6000 to 6500 feet.

Then drying and warming for next week, but with greater model spread on just how quickly and how much warming occurs.

Aviation

181030z, A band of RA mainly in San Diego County will continue to move east. In this band cigs 900-2500 feet MSL, vis 3- 5SM in RA. SHRA in deserts and areas of higher terrain obscured. Vcnty KSNA and KONT, SCT clouds around 3500-5000 feet. After 13Z, ISO- SCT SHRA from coast to mountains (SHSN in higher mountains), with bases locally 2500 feet MSL in precip. SHRA diminishes after 02Z but with ISO SHRA and locally BKN clouds around 3000 feet MSL overnight into Wednesday.

Marine

No hazardous marine conditions are expected through Thursday, but the next storm system has the potential to bring hazardous winds and seas Thursday night and Friday.

Beaches

Elevated surf of 3 to 5 feet, with sets to 6 feet on west-facing beaches is expected this morning, generating a high risk of rip currents.

Watches, Warnings, Advisories

Ca, Winter Weather Advisory until 10 PM PST this evening for San Bernardino County Mountains.

PZ, None.

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