textproduct: San Diego

SYNOPSIS

The marine layer will continue to deepen through tonight. This will bring a slight chance of light showers for late tonight and Wednesday morning for the coast and adjacent valleys. It will be cooler on Wednesday and breezy in the mountains and deserts, then dry and warmer for the Friday through the weekend. A low pressure system developing well off the California coast early next week could bring some precipitation by the middle or end of next week.

SHORT TERM (Today through Thursday)

For tonight and Wednesday, a low pressure system moving inland to the north will strengthen the onshore flow across southern California and deepen the marine layer. Low clouds for late tonight will spread into portions of the inland valleys with faster clearing for San Diego County on Wednesday morning. The HREF shows some light showers developing late tonight across the southern California coastal waters, spreading locally inland near the coast for Orange County northward. There will be stronger and gusty southwest to west winds for the mountains and deserts for Wednesday afternoon and evening with gusts to 25 to 35 mph along and below the desert slopes of the mountains with gusts to around 45 mph in the northern Coachella Valley below the San Gorgonio Pass.

High temperatures today will be slightly cooler, then as much as 4 to 8 degrees cooler on Wednesday for the valleys. High temperatures on Wednesday will range from the mid to upper 60s near the coast to the lower to mid 70s for the valleys with the lower deserts in the mid to upper 80s. On Thursday, the coast and valleys will begin to warm slightly while the mountains and deserts continue to cool slightly.

LONG TERM (Friday through Monday)

High pressure aloft will strengthen across California for the weekend. The greatest warming is expected on Friday for the inland valleys onto the lower coastal mountain slopes as the marine layer becomes shallower. There will be slight additional warming during the weekend. Sunday high temperatures will be mostly 5 to 10 degrees above average for inland areas, ranging from the lower to mid 70s near the coast to the 80s for the Inland Empire with the lower deserts around 90.

A low pressure system developing well off the California coast early next week could bring some precipitation by the middle of next week. NBM chances for measurable rainfall remain below 10 percent through Tuesday, then increase to around 20 percent on Wednesday and 50 percent on Thursday. For Wednesday and Thursday combined, NBM has around a 20 percent chance for one inch or more of rainfall for Big Bear with snow levels falling from around 8500 feet on Thursday to 7500 feet on Friday.

AVIATION

041630Z...Coasts/Valleys...Low clouds based at 800- 1200ft MSL and VIS 0-5SM will continue for coastal and western valleys through 17-18z. After, clouds clear back to the coast where they may linger through the afternoon. Low clouds with higher bases around 1200-1800ft MSL will push ashore 00-03Z, and spread into most of the coastal basin overnight into Wednesday. VIS reductions 0-5SM for inland valleys and coastal mountain slopes.

Mountains/Deserts...Mostly clear and VFR conditions today and tonight. Increasing high clouds AOA 20,000ft MSL late Wednesday morning and Wednesday afternoon.

MARINE

No hazardous marine conditions are expected through Saturday.

BEACHES

Long period (15-16 sec) west-northwest (290 degree) swell will arrive Thursday, peak Thursday night, and gradually diminish Friday. Surf of 4-6 feet is expected, locally higher on west-facing beaches. This will present a high rip current risk.

SKYWARN

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

SGX WATCHES/WARNINGS/ADVISORIES

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