Using Surf-Forecast’s Historical Surf Data To Find The Most Consistent Waves On Earth
Using our statistical data for 7000 spots dating back to 2006, we can find those waves that break the most, with the best winds.
Surf Forecasts:
Grumari surfForecast / Rio de Janeiro / Brazil
48hr Weather and Surf, issued 8 pm Wednesday 17 Dec 2025 -03Forecast update in hr min s Forecast update imminent
Grumari surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Grumari sea temperature is
27.1° C
(Which is 2.5°C warmer than normal for this time of year)How big are the waves at Grumari today?
The current surf forecast for Grumari at 3AM is: 1.4m 9s primary swell from a South-southwest direction and 0.9m 7s secondary swell from a Southeast direction (forecast issued at 08:00pm December 17). The wind direction is predicted to be glassy and the swell rating is 2.
| Time (-03) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (18 Dec) | 4.5ft (1.3m) | 9s |
| Afternoon (18 Dec) | 4.5ft (1.3m) | 9s |
| Evening (18 Dec) | 4.5ft (1.4m) | 10s |
Table - waves today at Grumari. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Wed 17 | Thursday 18 | Friday 19 | Saturday 20 | |||||||||||||||||||||
| 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |   |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 8 | 8 | 8 | 9 | 9 | 9 | 9 | 9 | 11 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 10 | 10 | 10 | 10 | 10 | 9 | 6 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 323 | 488 | 454 | 304 | 311 | 251 | 245 | 277 | 408 | 363 | 301 | 248 | 220 | 181 | 177 | 146 | 103 | 158 | 59 | 102 | 75 | 72 | 49 | 47 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross | glass | glass | glass | glass | glass | glass | cross- on | cross | cross | cross- off | cross- off | cross- off | glass | cross- on | cross- on | cross- on | cross | cross | glass | glass | glass | cross- on | cross- on |
High Tide / height (m) | 1:59AM 1.05 | 1:38PM 0.95 | 2:34AM 1.08 | 2:10PM 0.98 | 3:06AM 1.10 | 2:41PM 1.01 | ||||||||||||||||||
Low Tide / height (m) | 7:44PM 0.16 | 8:22AM 0.36 | 8:20PM 0.11 | 8:57AM 0.35 | 8:56PM 0.07 | 9:32AM 0.35 | ||||||||||||||||||
Wed 17 | Thursday 18 | Friday 19 | Saturday 20 | |||||||||||||||||||||
| Sunrise | - | - | - | - | 5:03 | - | - | - | - | - | - | - | 5:03 | - | - | - | - | - | - | - | 5:03 | - | - | - |
| Sunset | 6:36 | - | - | - | - | - | - | - | 6:37 | - | - | - | - | - | - | - | 6:37 | - | - | - | - | - | - | - |
 |  |  | | | |  | | | |  |  | |  | | | | | |  |  | | | | |
Rain (mm) | 2 | 2 | - | - | 1 | 1 | - | - | 1 | 1 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 20 | 20 | 21 | 20 | 20 | 20 | 21 | 21 | 20 | 20 | 20 | 20 | 20 | 22 | 23 | 23 | 22 | 22 | 22 | 21 | 21 | 25 | 25 | 25 |
| Feels °C (?) | 21 | 22 | 23 | 22 | 22 | 22 | 23 | 23 | 21 | 21 | 22 | 22 | 22 | 24 | 24 | 23 | 23 | 24 | 25 | 23 | 23 | 28 | 26 | 26 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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