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Conditions at Upper Trestles in April
April: Long-Period Swell, Short Weather Windows
April brings some of the longest average wave periods of the year at 13.3s, with average height still 3.5ft (1.1m). Swell direction now shifts firmly into the optimal S/SSW/SW/WSW corner: WSW 40.6%, SW 21.5%, SSW 3.8%, with W 33.2% as the main non-optimal component. That means the underlying energy is excellent for Upper Trestles, clean and lined-up groundswell from the southwest. The catch is wind. Ideal conditions drop to just 22%. Onshore S/SSW/SW/WSW winds account for nearly 48%, and the daily WSW sea breeze is well established by spring. Water temperature dips to a cool 13.9°C as upwelling kicks in, air averages 15.5°C, and rain decreases to 0.66 mm/day. Surf quality is all about timing: get in before 9am, or wait for a spring eddy to produce a rare north wind and score 3-5ft (1-1.5m) Lowers at its best.
Average Spot conditions at Upper Trestles in April
Swell history for April
Wind history for April
Swell quality
Analyze the groundswell consistency at Upper Trestles during April. Based on historical data, there is a % probability of groundswell occurring this month. The chart below provides a detailed breakdown of the average wave height distribution, offering deep insights into the swell quality and surf potential you can expect at Upper Trestles for your next trip in April.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Upper Trestles for April. Our analysis shows that favorable offshore or side-shore winds coincide with surfable swell approximately % of the time. The accompanying graph illustrates the average size distribution of waves during these optimal wind windows at Upper Trestles.