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.

December at Inamuragasaki offers average surf conditions with a mean swell height of 1.2m and a decent period of 8.6s, providing moderately clean and rideable waves. The most consistent swells arrive from the ESE, SE, and SW directions, with the majority falling in the 0.5-1.5m range, though SW swells occasionally bring larger sets (1.5-2.5m+). Wind conditions are mixed—only 23% of the time is it ideal (typically light offshore ENE-E winds), but stronger onshore W-WSW winds (20-50+ kph) occur frequently and can create choppy or blown-out conditions. Expect shorter windows of cleaner surf, especially when ENE-E winds align with ESE-SE swells, while bigger SW-WSW swells often coincide with stronger onshore winds. Overall, December is surfable but requires patience for optimal sessions.