During the winter months the sun may be expected to shine about 50% of the time between sunrise and sunset, and the figure seldom goes above 60% during the rest of the year along the immediate coast. Inland, however, sunshine increases during the summer to 80% or more.

Most of the winter cloudiness is associated with migrating storms that move inland from the Pacific. The cloud patterns of these storms are essentially the same over all parts of the County. In the summer, however, the cloud patterns are more localized. Low clouds or fog persist during much of the summer in a narrow band offshore. Under typical summer conditions this cloudiness moves inland during the late afternoon and spreads across much of the county during the evening; higher elevations observe it as fog. By mid-forenoon the cloudiness starts to dissipate over inland portions of the County, and the cloud deck gradually receded toward the coast. By early afternoon the entire County is enjoying sunshine, except possibly a narrow band close to the ocean where the cloudiness may persist throughout the day.