On a seasonal basis, fog and low clouds are nearly twice as prevalent from June through November with the worst month being July during which some 15 days have fog and low clouds. Few fronts pass through Miramar, especially during the spring and summer months. Very often, even during the winter months, frontal passages are hailed only by extensive middle cloudiness. Precipitation consists almost exclusively of rain or rain showers associated with frontal passages from November through March. The dearth of rain, is however, considerably compensated by a deposit of some 15 inches of dew annually.
Temperatures are mild as befits a locale dominated by a marine layer which overlies a cold current.
The absolute maximum temperature was 111 degrees F, and occurred as might be expected during the Santa Ana condition in September. Surface winds undergo both seasonal and diurnal variations. East winds prevail at other hours. At night the winds become easterly again, or calm. Thus, due to the diurnal variation of the sea-land breeze, the prevailing winds shift from easterly in the winter and spring to westerly during the summer and fall.