Inamuragasaki - surf spot statistics

Inamuragasaki, Japan, offers surfable waves year-round, but conditions vary significantly across seasons. The best months for surfing are typically from September to March, when ground swell contributions are higher (20-29%) compared to wind swell dominance in summer. During this period, mean swell size hovers around 1.2-1.4m, providing more consistent and cleaner waves. September through November stands out as the prime window, with ground swell still present (24-26%) and marginally improved wind conditions (22-25% good winds). Winter months (December-February) bring slightly smaller swells (1.1-1.2m) and the worst onshore winds (bad wind conditions 77-81%), but ground swell remains reliable (22-24%). Summer (May-August) is less ideal, with wind swell dominating (68-89%) and smaller waves (1.2-1.3m), though August sees a temporary ground swell increase (29%). Wind conditions are generally poor year-round (75-83% bad winds), but autumn offers the least unfavorable winds. For advanced surfers, targeting September-November balances decent swell size, manageable winds, and a higher chance of ground swell. Early mornings or offshore wind days are key due to persistent onshore winds.

In September, Inamuragasaki offers decent surfing conditions with an average swell height of 1.4m and a solid 9.3s period, indicating consistent, well-formed waves. The primary swell directions are E, ESE, and SE, which deliver the majority of rideable waves in the 1-2.5m range, ideal for intermediate to advanced surfers. Wind conditions are favorable only 22% of the time, typically when winds are light or offshore (N, NNE, or NE at 0-20kph). However, the spot frequently faces onshore winds from S, SSE, and SSW, which can create choppy conditions. Stronger winds (>20kph) from NNE to NE may occasionally overpower smaller swells, while SW winds—though less frequent—can also disrupt clean waves. Overall, September provides a mix of manageable swells but requires timing sessions around wind shifts for optimal performance.