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.

August at Inamuragasaki offers inconsistent but occasionally rideable conditions for surfers. The average swell height is 1.3m with a decent period of 9.6s, indicating some potential for well-formed waves, especially when swells reach the 1-1.5m range. The primary swell directions are from the ESE (14.5% frequency in the 0.5-1m range) and SE (5.5% in 1-1.5m), which often provide the best shape for this spot. However, larger swells (1.5m+) are less common, with only around 18% of waves reaching this size. Wind conditions are a mixed bag—light to moderate offshore winds (ENE, NE) occur occasionally, but the wind is only ideal for surfing 18% of the time, while onshore SW winds (5-20kph+) can frequently degrade conditions. Expect mostly smaller, weaker waves with occasional clean, rideable peaks, particularly when ENE swells align with lighter winds. Advanced surfers may find a few good sessions, but beginners will face limited opportunities.