textproduct: San Diego

SYNOPSIS

Above average high temperatures will begin to cool on Thursday. For late Thursday night into Friday, a low pressure system moving inland through Baja will bring showers, some with locally heavy rainfall near the coast. A second low pressure system will bring increasing showers for Friday night into Saturday morning along with stronger and gusty winds for the coastal waters and for the mountains and deserts. Saturday night through Sunday afternoon will be relatively drier with the next low pressure system moving inland into California Sunday night and Monday.

SHORT TERM (Today through Friday)

Not much change in temperatures is expected for today with high temperatures as much as 10 to locally 15 degrees above average for the coast and western valleys in San Diego County. High temperatures for the coast and valleys will be in the upper 70s to upper 80s with inland coastal areas into the western valleys in the mid to upper 80s.

Cooling will begin to spread inland on Thursday with high temperatures for the coast and valleys in the mid 70s to mid 80s, in the lower deserts in the lower to mid 80s, and in the mountains in the 50s and 60s. Some patchy low clouds could return to coastal areas for late tonight into Thursday morning.

A low pressure system moving inland through northern and central Baja on Friday will bring showers to southwestern California for late Thursday night into Friday morning. Showers will continue into Friday afternoon with the greater coverage for the valleys into the mountains. Through Friday afternoon, rainfall could range from 0.10 inch or less in the mountains to 0.1 to 0.25 inch in the valleys to locally 0.50 to 1 inch near the coast.

Water temperatures over the inner coastal waters have plateaued in the mid 70s F since late October. That's now around 12 degrees F above the long-term average for this time in November. Records for daily warmest water temperature at Scripps Pier are now routinely broken by 5+ degrees F. Prior to this year, the latest water temperatures near coast have been as warm as they are now was in late September.

As cold air aloft moves across southern California for late Thursday night into Friday, most unstable CAPE values will over the coastal waters near the coast from northern Baja into southern Los Angeles County will increase to 500 to locally 1000 J/kg. The RRFS and REFS show the potential for intense showers to develop over the coastal waters just off the coast from after midnight Thursday night into Friday morning with those showers with locally heavy rainfall moving inland into adjacent coastal areas.

NBM probabilities for 1 inch or more of rainfall from Thursday night through Friday afternoon are highest along the coast of San Diego into southern Orange County at 25 to 35 percent with the chance for 2 inches or more around 10 percent along the coast from northern San Diego County into far southern Orange County.

LONG TERM (Friday night through Tuesday)

A second low pressure system to the north will move quickly into California for Friday night and Saturday. Showers will increase for Friday night into Saturday morning, then decrease Saturday afternoon. Additional rainfall from Friday night through Saturday afternoon could range from around 0.50 near the coast to 0.50 to 1 inch on the coastal slopes of the mountains. That system for Saturday could also bring stronger winds to the coastal waters for Friday night and for the mountains and deserts for late Friday night through Saturday.

Saturday night through Sunday afternoon should be relatively drier. But the next low pressure moving into California will arrive on Sunday night and Monday. Still more low pressure systems moving inland along the West Coast next week will bring additional chances for precipitation, but with greater model spread on the track and timing.

AVIATION

111100Z...Mostly clear and VFR conditions today and tonight, except for patchy fog near the coast after 08Z Thursday.

MARINE

No hazardous marine conditions are expected through Friday. Onshore winds increase late Friday and seas build Saturday, which are likely to generate hazardous boating conditions. Winds diminish late Saturday and seas diminish late Sunday.

BEACHES

A series of swells from the west-northwest will generate higher surf starting Friday, likely producing hazardous surf conditions that will last into next week. Stay tuned for updates.

SKYWARN

Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.

SGX WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...None.