Lower Trestles - surf spot statistics

Best Surf Season (November - February)

Lower Trestles hits its stride from late fall through mid-winter as the North Pacific rumble to life. The combination of powerful, long-period groundswells from the WSW and SW quadrants meets the highest frequency of offshore winds (N, NNE, NE) — peaking at 59% ideal conditions in December. These months deliver consistent 1-1.5m fun-to-solid waves with periods often exceeding 12 seconds, making for rippable A-frames and long walls. The occasional bigger episode from a bomb cyclone can push the reef into pumping 1.5-2.5m territory, though W-dominant swells still require some luck to align with the preferred southerly band.

Fair Surf Season (October & March)

Shoulder months offer a mixed bag. October sees a ramp-up in S/SSW swell energy (9% combined from S/SSW) and improving wind chances (36% ideal), while March retains a good supply of WSW and W swell (83% combined) but offshore wind reliability drops to 31%. These months can produce excellent days when a late-season cold front passes through, cleaning up the water and steering in long-period swell. Expect more variability — some days of clean, shoulder-high surf, others murky and onshore.

Low Surf Season (April - September)

From spring through early fall, Lower Trestles goes quiet. The North Pacific storm track shuts down and the predominant SW and WSW swell is often accompanied by persistent onshore flow from the S, SSW, SW, and WSW — the worst wind directions for this south-facing reef. Ideal wind percentages bottom out between 9% (June) and 14% (August). Swell heights average only 0.9-1.1m, mostly groveling 0.5-1m range, though the period remains surprisingly long (13-14s) thanks to distant Southern Hemisphere storms. The rare combination of a strong southern hemi groundswell with a coastal eddy or Santa Ana wind event can produce brief, fantastic sessions, but those are the exception, not the rule.

May: Long Period, Low Wind Reliability

May continues the southern hemi influence with a long period of 13.5s and average height 1.1m. Swell directions are highly favorable: SW 30.3%, WSW 39.5%, and W 22.1%. That’s almost 70% in the optimal to good range. Yet ideal wind drops to a meager 10%, with onshore flow from SW (19.0%) and WSW (22.4%) dominating. The rare day with NE or N offshore flow (combined <4%) can turn the small, long-period groundswell into clean, rippable lines. Most days you’ll find choppy waist-high surf as the May Gray marine layer keeps winds swirly. Patience is key.