Surf Forecasts:
Grumari surf forecast from 16 Sep 2026:
- Best quality surf: Friday 18 Sep, 3AM (local time) - 4.5ft (1.3m), 10s period, S swell with cross-offshore winds.
- Most powerful swell: Thursday 17 Sep, 3PM (local time) - 6ft (1.8m), 12s period, S swell with 902 kJ wave energy.
- Next surfable swell (1★+): Friday 18 Sep, 3AM (local time) - 4.5ft (1.3m), 10s period with S swell.
Best Forecast Surf Conditions for Grumari this week:
The surf forecast for Grumari over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Friday (Sep 18) at 3AM. The primary swell is predicted to be 1.3m and 10s period with a secondary swell of 0.7m and 12s. Another secondary swell of 0.8m and 5s is also forecast. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Grumari in the next 16 days are 1.8m 12s and forecast to arrive on Thursday (Sep 17) at 3PM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 2.1m 7s period and expected on Saturday (Sep 19) at 6PM.
| Wave Type | Time (-03) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 3AM (Fri 18th Sep) | 4.5ft (1.3m) 10s |
| Best Surf | 3AM (Fri 18th Sep) | 4.5ft (1.3m) 10s |
| Most Powerful | 3PM (Thu 17th Sep) | 6ft (1.8m) 12s |
Table - best surf conditions forecast for Grumari over the next 16 days.
Short Range ForecastLight rain (total 3mm), mostly falling on Wed morning. Warm (max 21°C on Fri afternoon, min 18°C on Wed night). Wind will be generally light. | Days 4-6 Weather SummaryLight rain (total 8mm), mostly falling on Sun night. Warm (max 32°C on Mon morning, min 19°C on Sat night). Winds decreasing (fresh winds from the W on Sun night, light winds from the NE by Mon night). | ||||||||||||||||||||
Wednesday 16 | Thursday 17 | Friday 18 | Saturday 19 | Sunday 20 | Monday 21 | Tuesday 22 | |||||||||||||||
AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map |  |  |  |  |  |  |  | ||||||||||||||
Wave Height (m) Direction Period (s) | S 10 | S 12 | S 11 | S 10 | S 12 | S 10 | S 11 | S 11 | S 10 | S 10 | S 10 | S 9 | S 12 | S 12 | S 13 | S 12 | SSW 11 | S 10 | S 10 | S 9 | S 9 |
Wave Graph  | |||||||||||||||||||||
 kJ | 131 | 566 | 698 | 414 | 902 | 332 | 403 | 332 | 244 | 154 | 88 | 41 | 77 | 66 | 51 | 44 | 24 | 19 | 17 | 15 | 6 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | on | cross-on | cross | cross-on | cross | cross | cross-on | cross | cross-off | cross | cross | cross-off | cross | cross-off | off | cross | cross-off | cross-off | cross-on | cross-off |
High Tide | 4:54PM0.93m | 5:46AM0.89m | 5:20PM0.85m | 6:40AM0.78m | 5:51PM0.76m | 12:06PM0.77m | 7:01PM0.68m | 12:31PM0.86m | 11:40PM0.74m | 12:55PM0.96m | 00:19AM0.86m | 1:18PM1.04m | 00:49AM0.98m | ||||||||
Low Tide | 11:30AM0.47m | 11:33PM0.29m | 11:58AM0.57m | 00:25AM0.36m | 1:49PM0.66m | 2:25AM0.42m | 4:31PM0.65m | 4:26AM0.40m | 5:57PM0.57m | 5:42AM0.30m | 6:34PM0.48m | 6:31AM0.20m | 7:05PM0.39m | ||||||||
 | |  |  | |  |  | | | | | | | |  | |  |  | |  |  | |
 | 5:50 | — | — | 5:48 | — | — | 5:48 | — | — | 5:47 | — | — | 5:46 | — | — | 5:45 | — | — | 5:43 | — | — |
 | — | 5:47 | — | — | 5:47 | — | — | 5:47 | — | — | 5:49 | — | — | 5:49 | — | — | 5:49 | — | — | 5:50 | — |
mm | 2 | 1 | — | — | — | — | — | — | — | — | — | — | — | — | 6 | — | — | 2 | — | 1 | 3 |
Temp °C | 20 | 19 | 19 | 19 | 19 | 18 | 20 | 21 | 19 | 23 | 24 | 21 | 25 | 26 | 22 | 32 | 32 | 27 | 30 | 29 | 21 |
Feels °C | 20 | 18 | 18 | 18 | 18 | 17 | 19 | 19 | 18 | 23 | 23 | 21 | 25 | 26 | 22 | 32 | 33 | 30 | 32 | 30 | 21 |
Swell 1 Height (m) Direction Period (s) | S 10 | S 12 | S 11 | S 10 | S 12 | S 10 | S 11 | S 11 | S 10 | S 10 | S 10 | S 9 | E 7 | E 8 | E 8 | E 8 | E 8 | E 8 | E 8 | E 8 | E 8 |
| kJ | 131 | 566 | 698 | 414 | 902 | 332 | 403 | 332 | 244 | 154 | 88 | 41 | 246 | 191 | 212 | 145 | 157 | 82 | 130 | 86 | 68 |
Swell 2 Height (m) Direction Period (s) | ESE 8 | E 8 | ESE 11 | S 14 | ESE 10 | S 12 | ESE 8 | — | — | S 15 | S 14 | S 13 | S 12 | S 12 | S 13 | S 12 | SSW 11 | S 10 | S 10 | S 9 | S 9 |
| kJ | 51 | 34 | 68 | 181 | 54 | 138 | 41 | — | — | 4 | 16 | 30 | 77 | 66 | 51 | 44 | 24 | 19 | 17 | 15 | 6 |
Swell 3 Height (m) Direction Period (s) | SE 8 | SE 9 | S 16 | ESE 10 | SE 8 | ESE 10 | — | — | — | S 15 | — | SSW 9 | S 8 | S 14 | SE 14 | — | — | — | SE 13 | SE 13 | S 12 |
| kJ | 34 | 37 | 79 | 58 | 3 | 51 | — | — | — | 4 | — | 17 | 12 | 32 | 7 | — | — | — | 7 | 7 | 3 |
Wind waves Height (m) Direction Period (s) | SSW 6 | S 7 | — | — | — | E 4 | ESE 5 | ESE 6 | E 6 | E 6 | E 7 | E 7 | — | — | — | NNW 2 | — | SE 4 | N 3 | — | WSW 4 |
| kJ | 34 | 107 | — | — | — | 22 | 50 | 141 | 221 | 144 | 316 | 361 | — | — | — | 1 | — | 11 | 3 | — | 4 |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 82 | 159 | 63 | 5 | 5 | 5 | 5 | 122 | 6 | 0 | 122 | 5 | 0 | 6 | 6 | 0 | 8 | 2 | 2 | 34 | 2 |
Best forecast wave conditions in Rio de Janeiro | |||||||||||||||||||||
Best forecast wave conditions in Brazil | |||||||||||||||||||||
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The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Grumari surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
Information about the Grumari Surf forecast
The above surf forecast table for Grumari provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Grumari can be found by selecting the local surf guide option on the grey menu. Our Grumari surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Grumari) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).
Further information to help with frequently asked questions about our surf forecast for Grumari may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.
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