Lower Trestles - surf spot statistics

Lower Trestles is a consistent surf spot with predominantly ground swell year-round, though the optimal conditions vary across seasons. The best months for surfing are typically from March through September, when ground swell occurrence is highest (82–96%) and swell size averages around 0.8–0.9m. However, wind conditions play a crucial role, with onshore winds (bad conditions) dominating most of the year. The most favorable wind conditions are found in September and October, when good wind percentages reach 40%, though even then, offshore winds remain a minority. Late spring and early summer (May–June) see the strongest swells (0.9m), but wind quality drops significantly (only 26% favorable). Winter months (November–February) offer slightly better wind ratios (32–36% good), but swell consistency and size decrease, with more no-swell or wind-swell days. Ultimately, September and October strike the best balance, combining reliable ground swells (89–95%) and the least unfavorable winds (40% good), while still maintaining decent swell heights around 0.7–0.8m. For surfers prioritizing clean conditions over raw swell size, these transitional months are the most dependable.

December at this spot typically sees a mix of rideable conditions, though with some variability. The average swell height is 0.7m with a long-period 14.0s energy, suggesting well-formed, softer waves when they arrive—ideal for performance surfing or a more forgiving ride. The majority of swells come from the SSW, SW, and WSW directions, contributing to the spot’s consistency, with the largest share of waves falling in the 0.5-1m range, offering manageable yet fun conditions. About 32% of the time, winds align favorably—typically light offshore or cross-shore—enhancing wave shape. While bigger days (1.5m+) are rare, they’re cleanest when winds stay under 20kph, which happens frequently, especially from NE to E directions. Expect occasional onshore winds (W, WNW) that can disrupt conditions, but December remains a solid month for surfers who prioritize quality over size, with plenty of mid-sized, groomed waves.