Playa de San Juan - surf spot statistics

Best Surf Season (October - March)

The North Atlantic winter storms fire up from October through March, delivering consistent, long-period swell to Playa de San Juan. With the beach facing NNE, the most reliable swell directions come from the NNW, N, NNE, and NE, which together dominate the swell window during these months. Average wave heights range from 1.3m to 1.7m with periods averaging 10.6 to 12.7 seconds – often in the powerful long-period range. Critically, these months also see the highest frequency of offshore winds from the S, SSW, and SW, especially in December (12% ideal) and January (8%). When a low pressure system over the Bay of Biscay or a strong Atlantic storm sends NNW swell and the wind clocks around to the south, the points and beachbreaks at San Juan light up with punchy, rippable waves. However, the dominant wind pattern is still from the NNE (onshore), so patience is key – waiting for those rare but rewarding south wind windows.

Fair Surf Season (April, May, September)

The transition months of April, May, and September offer a mix of fading winter swell and rising summer conditions. Average wave heights dip slightly (1.2-1.5m) and periods moderate (9.1-10.6s). Swell direction remains mostly from the north quadrants, but the percentage of ideal offshore wind drops to 3-6%. April still packs a punch with occasional NNE swell in the 1.5-2m range and a 10.6s average period, but the increasing incidence of onshore NE trade winds often spoils the shape. May sees a significant drop in wave quality as the wind becomes almost exclusively onshore from the N and NNE (over 70% of the time). September marks the beginning of the autumn transition: swell periods lengthen to 9.5s and the first hints of southern wind return, but still only 4% ideal conditions. These months require a sharp eye on synoptic charts – you might score a clean, glassy session when a weak low pushes south winds over the region.

Low Surf Season (June, July, August)

The summer months are the leanest time for surfing at Playa de San Juan. Wave heights average just 1.2-1.4m with short periods of 7.3-8.1 seconds, resulting in weak, windswell-driven surf. The swell direction is almost exclusively from the N and NNE, which would be optimal if not for the prevailing wind. Unfortunately, onshore winds from the N and NNE dominate with a vengeance – in July and August, ideal offshore wind is effectively 0%, and the wind blows from the north sector over 90% of the time. This creates a constant battle of choppy, onshore conditions that make waves close out. Occasionally a distant southern hemisphere swell or a rare thermal gradient can produce a light SSW breeze, but such events are extremely rare. For the dedicated surfer, summer is best spent on alternative activities or chasing the few early morning windows before the sea breeze kicks in. The surf is small, weak, and mostly unsurfable – a true low season.

May: Fading Hopes

May marks a distinct downturn in surf quality. The average height falls to 1.3m, period drops to 9.1s, and ideal wind plummets to 3%. Swell direction remains north-dominated, with NNE at 30.1%, N at 24.9%, and NNW at 33.3%. However, most of this swell is in the 0.5-1.5m range, with only about 18% over 1.5m – a lot of groveling conditions. The wind shifts decisively onshore: NNE at 38.5% and N at 32.3% combine for over 70% of the time, often at 20-30 kph. Any wave quality is usually ruined by a bumpy, choppy surface. The rare south wind events (1-2% from SSW/SW) can make for fun, clean surf on the small swell, but they are fleeting. May is a month for the optimist with a log under the arm – expect micro to fun-sized waves and hope for a lucky south wind morning.