The mild climate from San Diego to Point Arguello is controlled by the Pacific high-pressure system. Aided by the sea breeze, it brings winds from off the water, mainly S through N, which help keep coastal temperatures up in winter and down in summer. Coldest average temperatures range from the middle to upper fifties (12.8 degrees to 15.0 degrees C), while summertime readings are most often in the seventies (22 degrees to 16 degrees C). Occasionally a hot dry flow off the land in autumm will cause temperatures to soar into the nineties (33 degrees to 38 degrees C), and a rare winter outbreak from the E can drop temperatures to below freezing (< 0 degrees C). Winter is the rainy season, although not much rain falls along the coasts.
Strong winds and rough seas, while less frequent than farther N, can be a problem from the middle of fall through late spring. Strong pressure gradients, distant storms, and infrequent close storms account for most of the gales and seas of 12 feet (3.7 m) or more, particularily off Point Arguello and in the Santa Barbara Channel. Strong local winds (Santa Ana) also generate gales along sections of this coast.
Advection or sea fog, formed by warm moist air flowing over cool water, frequently confronts mariners in these waters. It is a persist and widespread problem, particularly in the summer and fall N of Santa Monica, and in fall and winter S of Santa Monica.
Tides and Currents
Average tidal rise at HW is 1.5 m (5'). The max. tidal height is 2.3 m
(7'06").The tidal streams generally follow the direction of the
channel and attain rates of 0.5-3.0 knots.
The currents set generally in the direction of the channels. In the
vicinity of the entrance the usual velocity varies from 0.5 to 3 knots
depending upon the stage of the tide. South of the end of the jetty there
is a slight set toward Zuniga Shoal on the ebb. Great care should be taken
while passing Ballast Point as a vessel may take a sudden sheer because of
a crosscurrent deflected from Ballast Point.