Below average temperatures will allow for AM areas of frost in the San Diego Valleys and the Inland Empire. For the coastal areas: 40 to 44, western valleys and inland Orange County: 38 to 42, inland valleys: 35 to 42, mountains between 4000 ft and 7000 ft: 30 to 40, high desert: 31 to 39, low desert: 40 to 50.