Cloudy La Jolla cove
La Jolla Cove on a cloudy day. Photo from Wikimedia Commons.

A deep marine layer will keep much of San Diego County overcast and temperatures cool through Tuesday.

The National Weather Service reported patchy drizzle on Monday morning from downtown San Diego “over the far inland valleys” and said low clouds would remain throughout the day.

“A deep marine layer and only partial clearing west of the mountains today will keep SoCal on the cool side again for late September” the weather service said.

High temperatures on Monday were forecast to be 67 to 72 near the coast, 71 to 76 inland, 75 to 80 in the valleys, 74 to 83 in the mountains, and around 94 in the deserts.

“Below average high temperatures will continue through Tuesday with well below average high temperatures for the valleys,” the weather service said.

A large, low-pressure trough was expected to develop through the first half of the week, maintaining onshore flow, a deep marine layer, and cooler than average days.

Northwest winds were expected to increase Tuesday over the outer coastal waters, with gusts near 20 knots possible.

A south-southwest swell was predicted to bring elevated surf and a high risk of rip currents to the beaches Monday into Tuesday. Surf was expected to gradually diminish Tuesday through Wednesday.

A noticeable warm-up was predicted Thursday and Friday with weak Santa Ana conditions.

City News Service contributed to this article.

Updated at 7:45 a.m., Monday, Sept. 27, 2021