Despite its coastal location, Santa Monica doesn't fit the "foggy and freezing" stereotype. Its Mediterranean climate delivers mild, sunny days and cool—but not cold—nights year-round.
Beach (Santa Monica Pier, Will Rogers): Coolest, foggiest, windiest.
Inland (Montana Ave, Brentwood, West LA): Warmer, sunnier, less marine influence.
Canyons (Topanga, Pacific Palisades): Wider day/night swings, more fog retention.
Pack layers, not parkas. A light jacket suffices for evenings. The "foggy and very cold" description fits San Francisco or London better. Santa Monica is gentle—one reason it's been a lifestyle magnet for a century.