Seal Beach • Statistics for May

May: Southern Hemisphere Groundswell Gets Blown Out

May is the beginning of the long summer struggle. The swell signal still looks solid on paper - average height 3.3ft (1.0m), average period 13.7s - and the direction mix is now firmly in the southern hemisphere camp: SW 32.8%, WSW 38.2%, SSW 12.3%, W 16.6%. Those long-period SSW/SW lines are exactly what a SSW-facing beach wants to see. But the wind is terrible: only 3% of May observations are ideal. The thermal low strengthens and a persistent SW/WSW sea breeze dominates, with SSW at 18.0%, SW at 24.0% and WSW at 17.9% of all wind observations. That means the same swell that could be epic is instantly chopped into a lumpy, onshore wind-cloaked mess. Very occasional dawn patrols with light/variable winds can produce clean 3-4ft (1-1.2m) waves, but expectations should be low. Air temps rise to 16.4°C, water warms to 14.8°C, and rainfall is essentially absent (0.24 mm/day).