Waikiki Beach • Statistics for May

May: Trade Swell Peaks with a Broad Easterly Spread

May brings a classic trade-wind swell pattern. Average heights sit at 5ft (1.5m) with a period of 11.5 seconds. The dominant swell directions are E at 27.0%, ENE at 15.9%, ESE at 15.5%, and SE at 11.0%, with SSE at 11.5% and S at 7.6%. This is a broad spread of easterly and southeasterly energy, mostly generated by strong trade winds over the open Pacific. Most swell is in the 3.3-6.5ft (1-2m) range, with the E direction supplying 14.6% of 5-6.5ft (1.5-2m) energy.

Surf quality is limited by wind. The ENE trades account for 60.3%, and NE/E add another 24.3%, leaving just 14% ideal offshore conditions. For this north-facing exposure, the broad E/ESE/SE spread is not the optimal window, and the persistent trade texture keeps the surf from being truly clean. Air temperatures warm to 24.3°C, water to 25.2°C, and precipitation drops to 1.23mm/day. If you can find a morning glass-off or a temporary trade-wind breakdown, there are still fun, rippable waves to be had.