Strengthening onshore flow over San Diego County that began Saturday was expected to deepen the marine layer an cause progressively cooler weather into next week, the National Weather Service said.
Some patchy drizzle could break out Sunday night as a marine layer spreads fog and clouds well up the coastal mountain slopes, forecasters said.
A slow-moving storm system was predicted to increase the chances for rain and mountain snow from late Tuesday through Wednesday and keep daytime temperatures well below normal, the weather service said.
Cool weather and showers may linger through Friday night before dry and slightly warmer weather returns next weekend.
Highs on Sunday were forecast to be 62 to 67 along the coast, 63 to 68 inland, 60 to 67 in the mountains and 78 to 83 in the deserts.
The large trough was expected to slowly dip southward toward Southern California midway through next week.
“If you think the weekend will be a bit cool, get ready for the middle of week,” forecasters said. “Temperatures are not looking that warm, with highs struggling to reach 60 for many areas west of the mountains and only 30s and 40s for the mountains.”
Clouds and showers will start to overspread the region as early as Tuesday afternoon from west to east, the weather service said.
“San Diego County looks to be the hardest hit, with much of the coast and valleys looking to get close to one inch of rain in total,” forecasters said. “Snow levels will start out a bit over 4,000 feet on Tuesday and sink to around 3,500 feet early on Wednesday after going back up to 4,000 feet later on Wednesday into Thursday.”
Areas near 6,000 feet may see 4 inches of storm total snow or more, with some areas above 8,000 feet seeing 8 inches or more.
City News Service contributed to this article.
