Grumari - surf spot statistics

Grumari, Brazil, offers surfable conditions year-round, but the best months for consistent surf are typically from April to July. During this period, ground swell frequency peaks (51-58%), providing cleaner, more organized waves, while wind swell remains moderate (41-52%). Mean swell size also increases to around 1.5-1.6m, offering better wave power. Wind conditions during these months are not ideal but manageable, with 25-30% of days having favorable offshore or light winds, though onshore winds dominate. The worst wind conditions occur from August to November, where unfavorable winds exceed 80% of days, often causing choppy surf despite decent swell. From December to March, wind swell dominates (63-69%), resulting in less consistent wave quality, though still surfable, especially when ground swell contributes. September stands out with the largest mean swell (1.7m) but suffers from the highest percentage of bad winds (85%). For the best balance of swell size, ground swell dominance, and less terrible wind conditions, May and June are the top months—offering a solid mix of wave energy and occasional clean conditions. Early mornings or late evenings may provide better surf due to lighter winds. Overall, intermediate to advanced surfers will find the most rewarding sessions in late autumn and early winter (April-July), while other months require patience with wind and swell variability.

April at Grumari offers decent surfing conditions with an average swell height of 1.5m and a solid period of 10.6s, indicating consistent and well-formed waves. The swell direction is predominantly from the south and southeast, with the most frequent and powerful waves (1-2.5m) coming from the S and SSE. About 26% of the time, winds are favorable (light to moderate offshore or cross-shore), mainly from the north and northeast, though stronger onshore winds from the east and southeast can occasionally degrade conditions. Expect a mix of surfable days with clean, mid-sized waves when winds cooperate, but also some wind-affected sessions, especially during periods of stronger easterly flow. Overall, it's a moderately reliable month for surfers who can time the best conditions.