A summer heat wave will coincide with a large south swell this week in San Diego County, driving people to the coast where treacherous rip currents will roil near shore waters from Oceanside to Imperial Beach, says the National Weather Service. An excessive heat warning will be in effect in all areas except the coast from 10 a.m. Monday until 8 p.m. on Thursday. Temperatures will range from the 80s at and near the coast to the 90s and low 100s in some inland valleys and foothills, the weather service says. Temperatures will peak on Tuesday and Wednesday.