Choshi - surf spot statistics

Best Surf Season (October - March)

The winter months deliver the most consistent offshore wind conditions thanks to the strengthening Siberian High. Average wind ideal rates climb to 40-47% from November through January, with winter storms spinning up across the North Pacific and sending long-period groundswell. While the dominant swell direction is from the northeast, the south-facing beaches of Choshi still pick up a mix of ENE and E swell that can produce punchy, rideable waves. The average wave period hovers around 9.5-9.9s, offering solid power. Still, when a storm tracks favorably, we can see SSW or SW swell with offshore N winds - that is when the stars align for Choshi's best waves.

Fair Surf Season (April, September)

April sees a shift in the dominant swell window to more easterly and southeasterly directions, increasing the potential for good wave angles. September is a transition month where tropical systems in the Western Pacific can fire up SSE and S swells, often with light offshore winds early in the season. These months average 1.6-1.7m wave heights with periods around 9.2-9.4s, providing fun-sized conditions for the dedicated surfer, though the wind ideal percentage drops to 26-35%.

Low Surf Season (May - August)

Summer in Choshi is dominated by the East China Sea monsoon pattern, bringing persistent S to SW winds that are mostly onshore. While the swell direction turns favorable toward SE and S, the wind quality deteriorates significantly, with ideal wind rates dropping to 25-31%. Wave heights average 1.2-1.4m and periods shorten to 8.6-8.9s, resulting in small, choppy conditions. Occasional typhoon swells can break the monotony, but they are usually accompanied by strong onshore winds and dangerous surf.

July: Tropical Swell Window

July continues the summer lull with an average height of 1.2m and period 8.9s. The swell direction becomes more favorable: SE (19.1%), ESE (24.3%), and SSE (13.4%) make up the bulk. But onshore SSW (18.5%) and S (10.3%) winds crush quality, with ideal wind only 28% of the time. Waves are mostly in the 0.5-1m and 1-1.5m range. Typhoon swells can suddenly deliver 2m+ SE swell, but they often bring strong onshore winds - a classic trade-off.