Osbourne - surf spot statistics

Best Surf Season (October – March)

The heart of winter delivers the most consistent and powerful swell to Osbourne. Average wave heights hover around 1.6–1.7 m with periods often reaching into the 8.6–8.7 s range, thanks to frequent extratropical cyclones tracking across the North Atlantic. These systems generate significant long‑period groundswell that can light up the east‑southeast facing beach. However, the offshore wind window (W‑NNW) is only open about 25 % of the time, so quality sessions are a game of patience. When a cold front passes and the wind swings west, the waves become clean, hollow and absolutely pumping.

Fair Surf Season (April – June & September)

Spring and early autumn offer a trade‑off: smaller but more rideable waves and a slightly higher chance of offshore breezes. April averages 1.4 m at 8.4 s, while September sees 1.2 m at 8.5 s. Wind‑favorable conditions occur 28–37 % of the time, making these months the most reliable for fun, rippable waves. Swell direction shifts south as the jet stream weakens, and while the dominant S‑SSW energy isn’t ideal, it still produces workable lines. Longboarders and shortboarders alike find plenty of fun‑sized surf.

Low Surf Season (July – August)

Summer brings the smallest surf of the year. Average wave heights drop to just 1.0 m with periods of 7.2–7.7 s – often choppy and groveling. Although the offshore wind clock ticks up to 41–45 % (the highest of any season), the swell is simply too weak to light up the spot in a meaningful way. Occasional tropical systems can inject a rare pulse of energy, but most days are best reserved for a paddle or a flat‑day session.

December: Winter’s Peak

December rounds out the year with the largest average swell: 1.7 m and 8.6 s period. Swell distribution is similar to January – SSW (14.7 %), SW (12.2 %), and S (10.2 %) dominate. Optimal E‑SSE swell contributes 20.1 %, mostly from powerful winter lows. Offshore wind odds sit at 24 %, with WNW (14.2 %), NW (13.4 %), and W (10.4 %) leading the way. The combination of strong westerly winds and massive, long‑period groundswell can produce the most epic conditions of the year – heavy, hollow waves well into the 2‑3 m range. But those days are rare; most of the time the wind is onshore from the south. Those who brave the cold and chase the charts are rewarded with scores of a lifetime.