Rio de Coyula • Statistics for September

September: Biggest Averages of the Year

September posts the highest average swell height of the year at 5-6ft (1.7m) with a period of 13.2s, keeping the surf in the powerful long-period category. SSW remains dominant at 57 percent, with S at 22 percent and SW at 12 percent, so the favourable south-to-west quadrant accounts for more than 90 percent of the wave energy. This is also the time when Eastern Pacific tropical cyclones can throw additional S/SW swell into the mix, pushing waves into the 2m-plus range on the best days.

Wind conditions hold up better than the calendar might suggest: ideal wind is 53 percent, with NW/NNW offshore mornings still common and the W/E sea-breeze patterns mostly light. Water temperature is 29.6°C and air temperature 28.7°C, but September is the wettest month with 7.48mm/day of rainfall. Despite the rain, this is a prime month for larger, more powerful south swells - just be ready for lumpy afternoon bumps and the occasional tropical storm swell.