The water at Newport Beach, California, is generally considered cool to mild, rarely reaching what most would call "warm" compared to tropical destinations. Temperatures peak in August and September, typically ranging from 18°C to 21°C (64°F to 70°F). During the winter and spring months, the water can drop significantly to around 13°C to 15°C (55°F to 59°F), making a wetsuit necessary for most surfers and swimmers. Even in the height of summer, the Pacific's cold California Current keeps the shoreline refreshing rather than balmy. For 2026 visitors, the "best" swimming experience is usually found in late August when the coastal air has warmed the shallow areas, but for anyone used to the Caribbean or the Gulf of Mexico, the water here will always feel brisk and invigorating.