Thunders - surf spot statistics

Thunders in Indonesia is a consistent and high-quality surf spot with reliable ground swells throughout the year. The best months for surfing are generally from May to September, when the swell is most potent and wind conditions are most favorable. During this period, ground swell dominates at 97–100%, ensuring clean, powerful waves with minimal wind interference. The mean swell size peaks at 1.9m in July, offering ideal conditions for experienced surfers. Wind conditions improve significantly from May onward, with good winds occurring 51–70% of the time, particularly peaking in July at 70%. Outside this window, from November to March, the swell remains strong but is accompanied by less favorable onshore winds, reducing rideable days. December to February still see decent ground swell (82–92%), but bad wind conditions prevail 62–76% of the time, making sessions more inconsistent. April and October serve as transitional months, offering a mix of solid swell and improving wind conditions. Overall, Thunders delivers year-round surf, but the prime months are mid-year, with July standing out as the peak for both wave quality and wind reliability.

In January, Thunders in Indonesia offers consistent surf with an average swell height of 1.4m and a solid period of 13.3s, providing well-formed, powerful waves. The swell direction is predominantly from the SSW (34.93% in the 1-1.5m range and 8.63% in the 0.5-1m range) and SW (19.55% in the 1-1.5m range, with some bigger sets at 1.5-2m). Larger swells (2-2.5m) occasionally push in from WSW and W, though they are less frequent. Wind conditions are favorable only 26% of the time, with the most challenging winds coming from WNW and NW at moderate to strong speeds (10-30kph), which can create cross or onshore chop. However, lighter winds (0-10kph) from varying directions occur often, allowing for cleaner conditions when paired with the right swell. Overall, January delivers quality waves but requires patience for optimal wind alignment.