
Surf Forecasts:
Big Bay surf forecast from 6 Sep 2026:
- Best quality surf: Sunday 6 Sep, 8AM (local time) - 7ft (2.1m), 18s period, SW swell with offshore winds.
- Most powerful swell: Saturday 12 Sep, 5PM (local time) - 8ft (2.5m), 16s period, SW swell with 3,502 kJ wave energy.
- Next surfable swell (1★+): Sunday 6 Sep, 8AM (local time) - 7ft (2.1m), 18s period with SW swell.
Best Forecast Surf Conditions for Big Bay this week:
The surf forecast for Big Bay over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Sep 06) at 8AM. The primary swell is predicted to be 2.1m and 18s period with a secondary swell of 1.1m and 9s. The wind is predicted to be offshore as the swell arrives.
The most powerful waves expected at Big Bay in the next 16 days are 2.5m 16s and forecast to arrive on Saturday (Sep 12) at 5PM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.6m 6s period and expected on Thursday (Sep 10) at 2PM.
| Wave Type | Time (SAST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 8AM (Sun 6th Sep) | 7ft (2.1m) 18s |
| Best Surf | 8AM (Sun 6th Sep) | 7ft (2.1m) 18s |
| Most Powerful | 5PM (Sat 12th Sep) | 8ft (2.5m) 16s |
Table - best surf conditions forecast for Big Bay over the next 16 days.
The Lowdown
Alright folks, Rusty here. Let’s have a look at what’s cookin’ for the next couple of weeks.
We’ve got a solid run of swell ahead, but it’s a bit of a mixed bag for quality. The first real standout is a classic, clean, long-period groundswell that’s gonna have Big Bay looking prime. The water temp is a nippy 55°, which is a solid 5° colder than usual for this time of year – so you’ll be wantin’ a thicker suit.
The session kicks off this Sunday, the 6th of September, with a beautiful 7ft SW groundswell rolling in at a very long 18 seconds. That’s a lot of energy (3066) and the wind is a gentle offshore from the ESE. The waves are gonna be clean and powerful, lookin’ excellent for experienced surfers, but at that size, it’s a bit much for the beginners. The optimum swell direction is SW, and that’s exactly what we’ve got. The crowd factor is “often”, so expect a few mates out there, but it’ll be worth it.
Sunday afternoon holds up nicely with a 6ft SW swell, still long period at 16 seconds (1929 energy) and a light SE offshore. Smooth conditions.
Monday morning, the 7th, is a stunner. The wind goes dead calm, glassy, with a 7ft SW swell (14 secs, 1504 energy). It doesn’t get much cleaner than that for a paddle out. The morning is the pick, as the wind swings cross-shore by the afternoon.
By Tuesday the 8th, the swell drops off into the 3ft range and the wind gets messy. We’re looking at a few days of marginal, small waves up to the 10th of September. Not great, but the energy is low (306 to 476).
Then Thursday the 10th sees a pulse of bigger, stronger swell, but the wind is a fresh cross-offshore breeze at 19 mph. The waves are 8ft from the WSW (15 secs, 3491 energy), but that wind is gonna put a bit of texture on the face. It’s clean, but it’s gonna be a bumpy ride. Still a solid option for the experienced crew.
The quality drops again from Friday the 11th through the 13th, with the swell hanging around the 6ft to 7ft mark but the wind playing games. It’s not the cleanest.
Now, we get another big pulse. Saturday the 12th has a nice clean morning with a 7ft SW swell (14 secs, 2216 energy) and a light SE breeze. That’s a good one.
But the real standout for the big stuff is Wednesday the 16th of September. It’s a big, powerful 10ft SW swell (14 secs, 4378 energy) with a gentle cross-offshore breeze. That’s expert territory only, but the energy is massive and the conditions are clean. It’s a beast of a day for the experienced surfer.
The 17th of September brings an 12ft SSW swell (5677 energy) but the wind is onshore, making it a messy, blown-out mess. Not worth the paddle.
The following week fades out. The swell drops back to the 5ft to 3ft range, and the wind is mostly onshore or cross-shore, offering only marginal to poor conditions. The very last day, Monday the 21st of September, shows a glimmer of hope with a 6ft SW swell (13 secs, 1382 energy) and glassy conditions in the morning. That’s a promising end to the run, but it’s a long way off.
So, your best bets are the clean, glassy morning of Monday the 7th, and the big, powerful, clean swell on Wednesday the 16th. The rest of the time, you’ll be picking through some average to windy conditions.
Rusty.
Short Range ForecastMostly dry. Warm (max 26°C on Mon afternoon, min 14°C on Sun morning). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 20°C on Wed afternoon, min 13°C on Thu night). Mainly fresh winds. | ||||||||||||||||||||
Sunday 6 | Monday 7 | Tuesday 8 | Wednesday 9 | Thursday 10 | Friday 11 | Saturday 12 | |||||||||||||||
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) | SW 18 | SW 16 | SW 15 | SW 14 | SW 13 | WSW 13 | WSW 12 | WSW 12 | SW 11 | SW 13 | WSW 13 | SW 12 | WSW 15 | WSW 15 | WSW 14 | WSW 13 | WSW 12 | SSE 8 | SW 14 | SW 16 | SW 14 |
Wave Graph | |||||||||||||||||||||
2946 | 1852 | 1547 | 1493 | 1155 | 454 | 294 | 140 | 172 | 342 | 295 | 1137 | 3246 | 3114 | 2109 | 1226 | 830 | 558 | 1736 | 3502 | 2527 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | off | off | off | glassy | cross | glassy | cross-on | cross | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off |
High Tide | 11:37AM1.12m | 00:03AM1.20m | 12:46PM1.27m | 1:05AM1.32m | 1:34PM1.43m | 1:53AM1.44m | 2:15PM1.57m | 2:33AM1.51m | 2:51PM1.66m | 3:10AM1.55m | 3:25PM1.70m | 3:44AM1.55m | 3:58PM1.68m | 4:17AM1.52m | |||||||
Low Tide | 5:54PM0.50m | 6:31AM0.35m | 7:02PM0.34m | 7:23AM0.22m | 7:50PM0.20m | 8:04AM0.12m | 8:31PM0.08m | 8:41AM0.05m | 9:08PM0.01m | 9:15AM0.02m | 9:42PM-0.01m | 9:48AM0.03m | 10:15PM0.01m | ||||||||
6:58 | — | — | 6:56 | — | — | 6:54 | — | — | 6:54 | — | — | 6:52 | — | — | 6:50 | — | — | 6:50 | — | — | |
— | 6:30 | — | — | 6:30 | — | — | 6:31 | — | — | 6:32 | — | — | 6:32 | — | — | 6:34 | — | — | 6:35 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 |
Temp °C | 19 | 25 | 23 | 24 | 26 | 22 | 26 | 25 | 19 | 18 | 20 | 15 | 17 | 17 | 15 | 15 | 17 | 13 | 19 | 21 | 15 |
Feels °C | 16 | 24 | 22 | 24 | 24 | 20 | 26 | 23 | 18 | 16 | 17 | 11 | 14 | 13 | 12 | 11 | 13 | 9 | 18 | 19 | 14 |
Swell 1 Height (m) Direction Period (s) | SW 18 | SW 16 | SW 15 | SW 14 | SW 13 | WSW 13 | WSW 12 | SW 11 | SW 11 | SW 13 | WSW 13 | SW 12 | WSW 15 | WSW 15 | WSW 14 | WSW 13 | WSW 12 | S 8 | SW 14 | SW 16 | SW 14 |
2946 | 1852 | 1547 | 1493 | 1155 | 454 | 294 | 117 | 172 | 342 | 295 | 1137 | 3246 | 3114 | 2109 | 1226 | 830 | 316 | 1736 | 3502 | 2527 | |
Swell 2 Height (m) Direction Period (s) | SSE 8 | SSE 9 | SSE 8 | SE 7 | — | SSW 12 | SSW 11 | WSW 12 | WSW 14 | W 11 | W 11 | SW 16 | — | SW 15 | SW 13 | — | SSW 11 | WSW 12 | SSE 7 | — | — |
120 | 77 | 56 | 11 | — | 303 | 156 | 140 | 140 | 21 | 9 | 65 | — | 104 | 88 | — | 101 | 508 | 44 | — | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | SW 18 | WSW 16 | S 10 | S 9 | SSE 9 | — | WSW 20 | — | — | — | — | — | SSW 10 | SSW 18 | — | — |
— | — | — | — | — | 13 | 26 | 49 | 27 | 8 | — | 38 | — | — | — | — | — | 68 | 436 | — | — | |
Wind waves Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | S 3 | S 3 | S 4 | S 5 | S 6 | S 6 | S 8 | S 8 | S 7 | SSE 8 | — | SSE 7 | — |
— | — | — | — | — | — | — | — | 2 | 6 | 18 | 71 | 112 | 273 | 852 | 451 | 491 | 558 | — | 121 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 39 | 39 | 0 | 14 | 399 | 221 | 0 | 400 | 0 | 0 | 118 | 0 |
Best forecast wave conditions in Cape Town | |||||||||||||||||||||
Best forecast wave conditions in South Africa | |||||||||||||||||||||
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Information about the Big Bay Surf forecast
The above surf forecast table for Big Bay provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Big Bay can be found by selecting the local surf guide option on the grey menu. Our Big Bay 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 (Big Bay) 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 Big Bay 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.
Big Bay is 8 km (5 miles) from the very large city of Robben Island. If you plan a holiday in Cape Town, look for hotels and other accommodation in Robben Island. Robben Island has rooms for a wide range of budgets as well as cheap car hire and transport links.










