Mejillones - surf spot statistics

Best Surf Season (October - March)

The North Atlantic roars to life during these months, delivering a consistent barrage of powerful, long-period swell to Mejillones' north-northwest facing beach. With average wave heights hovering between 1.7m and 2.2m and periods often exceeding 11 seconds, the potential for pumping and firing conditions is at its peak. The ideal offshore wind (S to SW) blows with moderate frequency, especially in December (23% ideal) and January (19%), creating clean, glassy faces when the synoptic setup aligns. This is undoubtedly the prime window for scoring the best waves of the year.

Fair Surf Season (April & September)

Transitional months like April and September offer a mix of fading winter swell and building autumn energy. Average heights drop to around 1.4-1.9m and periods shorten to 10-11 seconds, but quality windows still present themselves when a late-season low or early-season hurricane sends a clean NW swell. Ideal wind frequency drops to 5%, making these months more of a gamble. However, when conditions align, you can still find fun-sized waves with less crowd pressure.

Low Surf Season (May - August)

Summer brings a drastic reduction in surf potential. The North Atlantic storm track shifts north, producing negligible long-period groundswell. Average heights remain around 1.4-1.6m, but periods slump to 7.7-9.5s, resulting in predominantly choppy, messy wave conditions. Dominant winds shift to strong northerly quadrants (NNE, NE) that blow directly onshore, ruining any semblance of shape. Ideal offshore winds are nearly nonexistent (0-2% of the time). These months are best left for other activities unless a rare tropical system aligns perfectly – a true low surf season.

October: Autumn Energy Builds

October sees a significant uptick in surf potential. The average swell height climbs to 1.7m and period to 11.4s – powerful and long period for the most part. The swell rose shows a strong bias toward NNW (56.7%) and NW (16.6%), both perfect for Mejillones. The frequency of ideal offshore wind increases to 13%, as S and SW winds become more common during post-frontal setups. October is a month where the North Atlantic begins to roar again, with multiple low-pressure systems tracking across the basin. When a deep low in the Norwegian Sea aims a long-period NW swell south, and a high-pressure ridge sets up over Spain, the result is world-class waves with offshore wind. This is a fantastic month to be in the water.