10-day surf forecast with Strike Scores for Grumari, Rio de Janeiro, RJ, Brazil
Grumari is Rio de Janeiro's most pristine surf beach, an environmental reserve where big wave legend Carlos Burle has called his favorite local spot. The beach is protected from development, creating a natural sanctuary just an hour from the city center. The waves are versatile, handling various swell directions and producing both lefts and rights along the beach. Access is controlled and parking limited, which keeps the crowds manageable even on good days.
Best day in the forecast: 2026-08-09 with a score of 76/100 (Good)
Fair recommendation: Grumari has 3 Good days but no Firing days. Decent for a local session.
Perfect alignment: Swell from 180° is within 5° of optimal 180°.
Marginal size: 1.3m is 0.4m from ideal 1.7m.
Good period: 13s is 93% of ideal 14s. Clean, powerful groundswell.
Moderate offshore: 11 km/h from 23° (NNE). Still grooming but noticeable wind.
Groundswell-dominant conditions (clean, long-period waves).
Good surfable conditions at Grumari. 1.3m swell from 180° with manageable wind. Solid session guaranteed.
1.3m (4.3ft) swell from 180° (S) at 13s period
No alignment: Swell from 95° is outside workable range 135°-225°. Wrong swell direction for this spot.
Marginal size: 1.2m is 0.5m from ideal 1.7m.
Short period: 9s is below minimum 10s. Windswell-dominated (choppy, weak waves).
Moderate offshore: 15 km/h from 4° (N). Still grooming but noticeable wind.
Poor conditions at Grumari. Either swell direction (95°), size (1.2m), or wind (15 km/h from 4°) is unfavorable. Consider other spots or wait for better conditions.
1.2m (3.9ft) swell from 95° (E) at 9s period
Local wind-generated waves (choppy, short-period)
No alignment: Swell from 89° is outside workable range 135°-225°. Wrong swell direction for this spot.
Marginal size: 1.0m is 0.7m from ideal 1.7m.
Short period: 8s is below minimum 10s. Windswell-dominated (choppy, weak waves).
Moderate offshore: 18 km/h from 325° (NW). Still grooming but noticeable wind.
Poor conditions at Grumari. Either swell direction (89°), size (1.0m), or wind (18 km/h from 325°) is unfavorable. Consider other spots or wait for better conditions.
1.0m (3.3ft) swell from 89° (E) at 8s period
Moderate alignment: Swell from 197° is 17° off optimal 180°, workable but not ideal.
Marginal size: 1.7m is 0.0m from ideal 1.7m.
Moderate period: 11s meets minimum 10s but below ideal 14s. Some groundswell energy present.
Onshore/cross-shore: 13 km/h from 88° (E). Destroying wave quality. Offshore range: 270°-45°.
Poor conditions at Grumari. Either swell direction (197°), size (1.7m), or wind (13 km/h from 88°) is unfavorable. Consider other spots or wait for better conditions.
1.7m (5.6ft) swell from 197° (SSW) at 11s period
Moderate alignment: Swell from 194° is 14° off optimal 180°, workable but not ideal.
Marginal size: 2.3m is 0.6m from ideal 1.7m.
Perfect period: 14s is at or above ideal 14s. Long-period groundswell with maximum power.
Strong offshore: 21 km/h from 303° (WNW). Grooming but may make paddling difficult.
Good surfable conditions at Grumari. 2.3m swell from 194° with moderate wind. Solid session guaranteed.
2.3m (7.5ft) swell from 194° (SSW) at 14s period
Good alignment: Swell from 183° is 3° off optimal 180°, still within prime range.
Marginal size: 2.4m is 0.7m from ideal 1.7m.
Moderate period: 12s meets minimum 10s but below ideal 14s. Some groundswell energy present.
Onshore/cross-shore: 12 km/h from 123° (ESE). Destroying wave quality. Offshore range: 270°-45°.
Surfable but not special at Grumari. The 2.4m swell from 183° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
2.4m (7.9ft) swell from 183° (S) at 12s period
Moderate alignment: Swell from 190° is 10° off optimal 180°, workable but not ideal.
Too big: 3.5m exceeds maximum 2.5m. Risk of closeouts.
Onshore/cross-shore: 20 km/h from 190° (S). Destroying wave quality. Offshore range: 270°-45°.
Poor conditions at Grumari. Either swell direction (190°), size (3.5m), or wind (20 km/h from 190°) is unfavorable. Consider other spots or wait for better conditions.
3.5m (11.5ft) swell from 190° (S) at 12s period
Moderate alignment: Swell from 191° is 11° off optimal 180°, workable but not ideal.
Too big: 2.9m exceeds maximum 2.5m. Risk of closeouts.
Onshore/cross-shore: 8 km/h from 145° (SE). Destroying wave quality. Offshore range: 270°-45°.
Poor conditions at Grumari. Either swell direction (191°), size (2.9m), or wind (8 km/h from 145°) is unfavorable. Consider other spots or wait for better conditions.
2.9m (9.5ft) swell from 191° (S) at 11s period
Very low confidence (8-10 day forecast, conditions may change)
Good alignment: Swell from 185° is 5° off optimal 180°, still within prime range.
Too big: 2.6m exceeds maximum 2.5m. Risk of closeouts.
Onshore/cross-shore: 11 km/h from 76° (ENE). Destroying wave quality. Offshore range: 270°-45°.
Surfable but not special at Grumari. The 2.6m swell from 185° is workable, but conditions aren't ideal. Fine if you're local, but not worth a dedicated trip.
2.6m (8.5ft) swell from 185° (S) at 13s period
Marginal size: 2.5m is 0.8m from ideal 1.7m.
Onshore/cross-shore: 10 km/h from 82° (E). Destroying wave quality. Offshore range: 270°-45°.
Good surfable conditions at Grumari. 2.5m swell from 180° with manageable wind. Solid session guaranteed.
2.5m (8.2ft) swell from 180° (S) at 14s period
Open-Meteo Weather API (wind/weather data)