Sao Juliao - surf spot statistics

Best Surf Season (October - March)

The North Atlantic roars to life during this six-month window, delivering the most consistent and powerful surf of the year at Sao Juliao. Average swell heights range from 2.0m to 2.6m, with periods frequently in the 12-13 second range – a recipe for long-period groundswells that wrap into the WNW-facing beach with authority. The dominant swell directions are NW, WNW, and NNW, which together account for over 50% of the total swell energy in most months. This is when the jet stream is most active, spawning deep extratropical lows that send clean, lined-up waves to the Portuguese coast. Offshore wind conditions (from the E to SE quadrants) occur roughly 20-25% of the time, often during post-cold-frontal setups with light easterlies. When these align, expect pumping, heavy surf in the 1.5-2.5m range with epic, long-period waves that make the beach a world-class destination. The best windows are often in November, December, and January, when the NAO index can be negative, steering storms toward the Iberian Peninsula.

Fair Surf Season (April - May)

As spring arrives, the frequency of powerful low-pressure systems begins to wane, but the Atlantic still provides a steady supply of moderate-groundswell energy. Average swell heights drop to 1.7-2.0m, while periods shorten to 10-11 seconds, producing average, punchy waves that remain fun and rippable. NW and WNW swells still dominate, but the wind patterns become less reliable for perfect conditions. Ideal offshore easterlies occur only 9-12% of the time, as the dominant wind starts to shift from northerly (cross-shore) to more frequent sea breezes. Early-morning sessions often offer the best chance for clean faces before onshore winds pick up. This is a transition season – you’ll need to work for the good days, but when a strong spring storm aligns with a high-pressure ridge, you can enjoy solid surf with far less crowds than winter.

Low Surf Season (June - September)

The summer months bring a dramatic reduction in both swell size and quality. Average heights slide to a paltry 1.4-1.6m, and periods drop to 8-10 seconds – often producing choppy, weak, and messy waves. The swell direction remains locked in from the NW and NNW, but these are generally windswell or shorter-period pulses with minimal power. The real killer is the wind regime. A dominant northerly flow (N and NNW) sets in, blowing along the coast at 20-40 kph for the majority of days. This creates strong cross-shore to side-onshore conditions that spoil the wave shape. Ideal offshore easterly winds are a rarity, occurring only 2-5% of the time in July and August. The surf is generally limited to small, fun-sized groveling waves for the shortboard, or longboard glide on the rare, cleaner days. Dawn patrol is your only hope, as thermal-driven onshore winds develop quickly. With high pressure locked over the Azores, the summer pattern is reliable – but not for good surf. Plan your trip elsewhere or bring a log and low expectations.

January: Deep Winter Pulse

January is the apex of North Atlantic fury, with an average swell height of 2.6m (the highest of the year) and a commanding period of 13.0 seconds – firmly in the very powerful, long-period range. Swell direction is heavily clustered in the NW (21.9%), WNW (17.7%), and NNW (9.5%), producing a total of nearly 50% of waves from these optimal windows. This means consistent, groundswell-driven lines that wrap perfectly into the WNW-facing beach. Over 35% of waves fall in the 1.5-2.5m range, with another 10% exceeding 2.5m – pumping, heavy surf on tap. The wind is ideal a solid 25% of the time, the best of any month. Offshore easterlies (E to SE) collectively account for around 23% of wind observations, often arriving with light speeds of 10-20 kph after frontal passages. Northerly winds dominate the rest (13% from N, 10.8% from NNE) but these blow cross-shore from the north, often leaving the waves clean in the morning. Big swells from a deep low in the North Atlantic, combined with a high-pressure ridge over the continent, are your golden ticket for epic, pumping sessions. Watch for a negative NAO to steer storms directly toward Portugal.