Swell Matrix

Area Forecast Discussion

National Weather Service San Diego CA

1026 am PDT Thu apr 30 2026

Synopsis

High temperatures today around average for the coast to the mountains and around 5 degrees above average for the deserts will warm to 5 to 10 degrees above average for inland areas on Friday and Saturday. A low pressure system moving inland into California will bring cooling for Sunday and Monday with Monday high temperatures around 10 degrees below average for inland areas to 10 to 15 degrees below average for the mountains. Not much change for Tuesday, then warming to around average on Wednesday. There is a chance for mostly light showers at times from the coast to the mountains for late Sunday night through Tuesday afternoon. Onshore flow will be stronger for Sunday through Tuesday with southwest to west winds for the mountains and deserts gusting to 30 to 40 mph.

Discussion

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

New Aviation and Marine Discussion,

Short Term

(today through Saturday), Not much change for high temperatures today with high temperatures for the coast to the mountains within a few degrees of average with the deserts around 5 degrees above average. High pressure will bring warming for Friday with not much change on Saturday with high temperatures 5 to 10 degrees above average for inland areas. High temperatures on Saturday will range from around 70 near the coast to the 80s for the Inland Empire with the mid to upper 90s for the lower deserts.

Night and morning coastal low clouds will spread into portions of the inland valleys for today and Friday, then just into portions of the western valleys for Friday night into Saturday morning.

Long Term

(Sunday through Wednesday, A closed low pressure system moving southward off the California coast on Sunday will move slowly into central California on Monday and southern California on Tuesday.

There will be several degrees of cooling on Sunday with even greater cooling on Monday with not much change on Tuesday. High temperatures for Monday and Tuesday will be around 10 degrees below average for inland areas to as much as 10 to 15 degrees below average for the mountains. High temperatures for Monday and Tuesday will be mostly in the mid 60s to around 70 for the coast and valleys and in the mid 70s to lower 80s for the lower deserts.

There is a chance of mostly light showers at times for late Sunday night through Tuesday afternoon. Onshore flow will be stronger for Sunday through Tuesday with southwest to west winds for the mountains and deserts gusting to 30 to 40 mph.

High temperatures on Wednesday will warm to around average with high temperatures ranging from the mid 60s to around 70 near the coast to the mid 70s to lower 80s for the Inland Empire with the lower deserts around 90.

Aviation

301725z. Coast/Valleys, BKN-SCT clouds AOA 15K ft MSL moving south and east throughout the day. Low clouds will return to coastal San Diego County starting 02-06Z with slightly higher bases and spread northward near VCTY KSNA around 07-09Z. Low clouds based at 1500-2500 feet MSL should gradually fill much of the coastal basin by 12Z, scattering through the mid morning hours on Friday.

.Mountains/Deserts, Areas of elevated westerly winds 20-30 kts, with gusts to 40 kts through mountain passes and into adjacent deserts 00-10Z. Areas of up/downdrafts and isolated LLWS in lee of mountains.

Marine

No hazardous marine conditions are expected through Monday.

Watches, Warnings, Advisories

Ca, None. PZ, None.

Visit this site often? Consider supporting us with a $10 contribution.
Learn more