San Onofre State Beach - surf spot statistics

Best Surf Season (December - March)

Winter brings the most consistent combination of surf and offshore winds to San Onofre. With the North Pacific storm track firing on all cylinders, long-period groundswells from the W and WSW dominate, averaging 1.0-1.1m at 12.4-12.6s. While these swells aren't always perfectly aligned with the optimal S-SW window, the angles from WSW and W wrap nicely into the point. The real key is the wind: offshore flow from the N through ENE blows over 50% of the time in December and January, grooming the waves to perfection. The occasional Southern Hemisphere swell adds variety. This is the prime window for clean, rippable waves at San O.

Fair Surf Season (April, May, October, November)

Spring and fall offer transitional conditions. In spring, the south swell season begins to show life — April and May see increasing amounts of SW and SSW swell with longer periods (13.3-13.5s). However, the offshore wind window narrows dramatically (19% in April, 8% in May) as the Pacific high strengthens and onshore afternoon breezes become more frequent. Early mornings can still deliver clean waves before the wind kicks up. October and November see a reversal: offshore winds increase again (30% in Oct, 45% in Nov) as the high shifts, but swell from the W and WSW is still solid, though period drops slightly. These months provide a good balance but require picking the right tide and wind window.

Low Surf Season (June - September)

Summer is the most challenging time for consistent surf at San Onofre. While the southern hemisphere pumps out consistent long-period SW and SSW swell (periods 13.6-13.8s, heights around 1.0m), the onshore wind pattern dominates. The wind is ideal only 6-9% of the time, with persistent W and WSW winds creating choppy, bumpy surfaces. Despite the swell size being fun-sized, the poor wind conditions limit quality sessions to rare early morning offshore windows or when tropical systems align. It's a season for the dedicated dawn patrol and the occasional typhoon-swell winner.

May: South Swell Peak, Wind Struggle

May sees the peak of the southern hemisphere swell season with long-period groundswells averaging 13.5s. SW swell accounts for 30.3% of the energy, providing excellent lines at San O. Yet the wind is favorable only 8% of the time — the worst of the year. Persistent onshore winds from the W and WSW dominate, making it a month for dawn patrols and wind-swell windows. The rare offshore day delivers glassy, long-period perfection.