Forecasters expect below average temperatures for most parts of San Diego County through Thursday before another heat wave hits Southern California this weekend.

Highs Tuesday are forecast to be 76 to 80 near the coast, 80 to 85 in the western valleys, 76 to 85 in the mountains and 95 to 98 in the deserts, according to the National Weather Service.

Surf of 2 to 5 feet is expected with sets to 6 feet north of Carlsbad, forecasters said. High surf and hazardous swimming conditions will peak Monday through early Tuesday, lowering late Tuesday and Wednesday.

The marine layer will start quite deep and gradually become shallower through the week, with low clouds becoming more patchy and localized by week’s end.

High temperatures are forecast near to slightly above average Friday, according to meteorologists.

Forecasters predict another heat wave Saturday through Monday with Sunday being the hottest day. High temperatures will likely be 3 to 10 degrees above average — hitting triple digits in the low deserts.