Orio - surf spot statistics

Best Surf Season (October - March)

The heart of the Basque winter delivers the goods at Orio. As the North Atlantic storm track fires up, long-period NW and WNW swell trains march into the Bay of Biscay. With the beach facing NNW, these groundswells wrap in with power, often producing pumping 1.5-2.5m faces on the sets. The 42-44% of ideal wind (S to SSW) during these months is a huge plus – a classic Spanish swell-wind combo that sees offshore breezes grooming the lines into clean, hollow walls. December and January average a 2.1m swell with periods around 12.7s, meaning plenty of firing sessions. The NAO often goes negative, steering low pressures southward and feeding the Basque coast with consistent, high-quality surf. This is the prime window for charging.

Fair Surf Season (April - May & September)

As the seasons transition, the Atlantic energy begins to wane but still offers solid rideable waves. April and May see average heights drop to 1.5m and 1.2m respectively, with periods slipping to 10-10.8s. The wind remains favourable around 28-32% of the time, often from the south. You’ll still score fun, rippable 0.5-1.5m surf, especially on the better NW swells that manage to reach the coast. September is a gem – the first autumn lows start spinning, boosting average height back to 1.3m and periods to 10.4s, with 32% ideal wind. The water is still warm, and the crowds thinner than in winter. These months reward those who watch the charts closely for a synoptic setup that aligns a solid NW swell with a southern breeze.

Low Surf Season (June - August)

Summer settles in and the North Atlantic relaxes, leading to a prolonged stretch of small, weak surf at Orio. Average heights hover around 1.0m with short periods of 8.8-9.2s. The wind is ideal only 18-21% of the time, and the dominant NW wind (onshore for the spot) often ruins what little swell there is. The majority of waves come from the NW, but they are mostly in the small, fun-sized 0.5-1m range – better suited for a longboard or a groveler. The long-period groundswells are absent. Occasional weak fronts can provide a brief rideable pulse, but overall, the consistency and quality are low. This is the time for dawn patrol peace or exploring other spots if you need a proper wave.

December: Winter Peak Settles In

December closes the year with near‑peak conditions. Average swell height is 2.0m and period 12.4s. NW (28.1%) and WNW (24.4%) combine for over half the swell, with significant contributions from W (4.4%) and SW (1.6%) that wrap in. The wave height bands show a strong peak in the 1.5-2.5m range – pumping to heavy. Ideal wind is the highest of any month at 44%, with S (20.9%) and SSW (13.0%) providing dominant offshore flow. This creates clean, lined‑up waves with long, powerful walls. The synoptic setup is similar to January, with deep lows tracking across the North Atlantic and feeding the Bay of Biscay with constant long‑period energy. December is a pro-level month at Orio, offering consistent, large surf under favourable winds. The only downside is cooler air and water, but the wave quality more than compensates.