Guethary - surf spot statistics

Best Surf Season (October - March)

The North Atlantic swings into full production mode during these six months, delivering a steady diet of powerful, long-period swell to the NW-facing shores of Guethary. Average wave heights hover between 1.3m and 1.8m, with periods consistently above 11s and often reaching 13s, putting the spot firmly into the pumping and firing categories. The climatalogical dip in the Azores High allows low-pressure systems to barrel across the basin, sending trains of W, WNW, NW and NNW swell straight into the Bay of Biscay. Offshore wind windows – driven by continental high pressure or the eastern flank of passing lows – occur 41-50% of the time, perfect for grooming those long, clean lines. December stands out as the statistical peak, but every month from October through March offers ample opportunity for classic Guethary barrels.

Fair Surf Season (April & September)

April and September represent the shoulder months, where the ocean still holds respectable swell but the consistency and power begin to wane. Average swell heights drop to 1.1-1.2m, periods shorten to 10.6-11.0s, and ideal wind frequency falls to around 29%. Swell directions remain dominated by WNW and NW – the bread and butter for this spot – but the mix is peppered with more small, weak pulses. Spring and autumn transition patterns often bring fickle conditions: some days deliver punchy, rideable waves, others are plagued by onshore breezes from the W or NW. For the patient surfer, these months can still yield solid sessions, especially when a late-season storm sneaks through and a high-pressure ridge parks itself over the continent, producing offshore flow.

Low Surf Season (May - August)

Summer at Guethary is a classic tale of diminished energy. From May through August, average swell heights bottom out at 0.9-1.0m and periods slump to 9.0-10.1s, often producing small, fun-sized or groveling conditions. The dominant swell still arrives from the NW and WNW, but the fetch is generally weak – either from distant tropical systems or lightweight Atlantic lows. More critically, the percentage of ideal offshore wind plummets to 15-23%, as the prevailing regime shifts to spring/summer westerlies and sea breezes that ruin the wave face. While the occasional long-period groundswell can sneak in from a rogue storm, the day-to-day reality is small, wind-affected surf. This is the season to save your energy, explore other spots, or wait for the autumn equinox to reignite the North Atlantic machine.

October: Roaring North Atlantic, Prime Time Arrives

October is when the North Atlantic truly roars back to life. Average swell height jumps to 1.3m and period lengthens to 11.3s, with a healthy mix of heights: 27.1% of waves are 1-1.5m, and 18.5% are 1.5-2.5m from the combined WNW and NW directions. The swell direction is almost evenly split between WNW (41.2%) and NW (42.1%) – a perfect balance that lines up nicely with the spot’s exposure. Wind conditions become much more favorable: ideal offshore 41% of the time. The increase in SE to SSE winds (collectively ~16%) provides crisp side-offshore flow, while the persistent westerlies (W 10.5%) are still a factor but less dominant than in summer. The autumnal increase in storm frequency and intensity, often linked to a negative NAO pattern, sends long-period pulses marching into the Bay of Biscay. October is a prime month for Guethary: expect consistent, powerful swell with improving wind windows. The water is still warm from summer, the crowds are manageable before the winter peak, and the waves are firing.