San Onofre State Beach • Statistics for March

March: Stormy but Still Rippable

March marks the beginning of the spring transition, yet there is still plenty of punch in the water. The average swell height sits at 3.6ft (1.1m), with a 12.6s period, and the swell direction shifts further toward the optimal southwest quadrant: WSW is now 39%, SW 13%, and W has dropped to 44%. SSW adds another 2%, meaning nearly 54% of all swell energy is arriving from the directly favorable S through WSW window. The spread of wave heights is healthy, with the 3-5ft (1-1.5m) class especially well represented, and a secondary cluster in the 2-3ft (0.5-1m) range.

Wind quality takes a noticeable step backward compared to the winter months. The ideal wind frequency drops to 29%, and onshore flow from S through WSW now exceeds 30% of observations. Westerly winds also become more prevalent, adding cross-shore texture to the lineup. This is the month where you have to pick your windows: typically early morning before the sea breeze, or the day after a cold front passes. Air temperatures average 14.3°C, water temperature still sits at a chilly 14.2°C, and precipitation drops to 1.50 mm/day. The waves are still capable of quality, but the surface conditions are less reliable than in January.