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.

January at Inamuragasaki offers relatively small but surfable conditions, with an average swell height of 1.1m and a decent period of 8.2s, providing some energy for intermediate surfers. The most consistent swell direction comes from the ENE, WSW, and SW, with WSW swells bringing the largest waves (peaking at 2.5m+ in rare cases). However, the majority of waves are in the 0.5-1.5m range, with ENE swells being the most frequent. Wind conditions are only ideal 21% of the time, as strong northerly and westerly winds dominate, creating choppy or cross-shore conditions. The strongest winds come from N, NNE, and WSW, often exceeding 20-30kph, which can ruin wave quality. Cleaner sessions are more likely with lighter ENE or E winds. Overall, January is a mixed month—smaller but rideable on good days, though wind interference is frequent. Patient surfers may find some decent sessions, but expect mostly average conditions with occasional clean windows.