
Surf Forecasts:
Big Bay surf forecast from 5 Sep 2026:
- Best quality surf: Sunday 6 Sep, 2AM (local time) - 5ft (1.6m), 21s period, SW swell with offshore winds.
- Most powerful swell: Thursday 10 Sep, 11AM (local time) - 10ft (3.0m), 16s period, SW swell with 4,018 kJ wave energy.
- Next surfable swell (1★+): Saturday 5 Sep, 11PM (local time) - 3.5ft (1.1m), 22s 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 Saturday (Sep 05) at 11PM. The primary swell is predicted to be 1.1m and 22s period with a secondary swell of 0.4m and 10s. Another secondary swell of 1.7m and 9s is also forecast. 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 3.0m 16s and forecast to arrive on Thursday (Sep 10) at 11AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.2m 5s period and expected on Thursday (Sep 10) at 8AM.
| Wave Type | Time (SAST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 11PM (Sat 5th Sep) | 3.5ft (1.1m) 22s |
| Best Surf | 2AM (Sun 6th Sep) | 5ft (1.6m) 21s |
| Most Powerful | 11AM (Thu 10th Sep) | 10ft (3.0m) 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 the next 16 days for Big Bay. We’ve got a solid run of swell on the way, but it’s not all going to be clean. The water is sitting at 55°, which is a full 5° colder than normal for this time of year – that’s a big deal, so you’ll want a thick wetsuit, no question. Sunday morning is the first real standout, and we’ve got another banger lined up for the following Saturday.
The first real swell window opens up on Sunday, September 6th. The morning session is the pick of the opening run. A solid 7ft SW groundswell is rolling in with a long 18-second period, and the wind is offshore from the ESE at 9 mph. The water will be clean, and the combined energy is pumping at 3093. That’s a proper groundswell, so expect power and longer lulls between sets. This is excellent for experienced surfers; at 7ft, it’s too big for beginners.
Monday, September 7th morning is very special. The wind goes glassy, WNW at 3 mph, with a 6ft SW swell at 14 seconds. The energy is still strong at 1398. You’ll be surfing in absolutely perfect, clean conditions. The afternoon turns a bit cross-shore, but the morning is where it’s at.
Thursday, September 10th morning sees another pulse of bigger SW swell, hitting 10ft with a 16-second period. The combined energy jumps to 4018, which is powerful. The wind is cross-off from the SSE at 9 mph, keeping it clean. This is a serious, expert-only day. The swell is over 8ft, so if you’re not on your game, stay out.
The real standout, the one you circle on the calendar, is Saturday, September 12th. The afternoon is perfect. An 8ft SW swell at 16 seconds, with a clean offshore wind from the SE at 12 mph. The energy is a massive 3440, and the wind is described as "moderate offshore and clean." That’s as good as it gets for Big Bay. The morning is also excellent, but the afternoon is the winner.
Sunday, September 13th gets messy with cross-onshore winds, so that’s a write-off. We get a short burst of good conditions again on Thursday, September 17th, with a 6ft SW swell and light offshore winds from the ESE at 6 mph. The energy is 2276. It’s a good, clean option for a weekday.
The very end of the run, on Saturday, September 20th, sees a big 12ft SW swell, but with rain and strong cross-onshore winds. That’s a messy, powerful mess. The energy is 4401, but the wind is all wrong. It’s more of a kite-surfing day than a paddle day.
To sum it up: Sunday the 6th morning is great, Monday the 7th morning is glassy perfection, but the best on offer is the afternoon of Saturday the 12th. Get on it.
Rusty.
Short Range ForecastMostly dry. Warm (max 26°C on Mon afternoon, min 11°C on Sat morning). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 26°C on Tue afternoon, min 14°C on Wed night). Winds increasing (calm on Tue morning, fresh winds from the SSE by Thu night). | ||||||||||||||||||||
Saturday 5 | Sunday 6 | Monday 7 | Tuesday 8 | Wednesday 9 | Thursday 10 | Friday 11 | |||||||||||||||
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) | SSE 8 | SSE 8 | SW 21 | SW 18 | SW 16 | SW 15 | SW 14 | SW 13 | WSW 13 | WSW 12 | WSW 12 | WSW 11 | WSW 13 | WSW 13 | WSW 12 | SW 16 | WSW 14 | WSW 14 | WSW 13 | WSW 12 | SW 12 |
Wave Graph | |||||||||||||||||||||
532 | 207 | 2326 | 2946 | 1852 | 1343 | 1383 | 1155 | 454 | 294 | 140 | 151 | 304 | 265 | 691 | 4018 | 2878 | 1889 | 1250 | 878 | 558 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | off | off | cross-off | cross-off | glassy | cross | off | glassy | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off |
High Tide | 9:47AM1.03m | 10:28PM1.12m | 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 | |||||||
Low Tide | 3:58PM0.59m | 5:14AM0.47m | 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 | ||||||||
6:58 | — | — | 6:58 | — | — | 6:56 | — | — | 6:54 | — | — | 6:54 | — | — | 6:52 | — | — | 6:50 | — | — | |
— | 6:30 | — | — | 6:30 | — | — | 6:30 | — | — | 6:31 | — | — | 6:32 | — | — | 6:32 | — | — | 6:34 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 16 | 22 | 17 | 20 | 25 | 24 | 24 | 26 | 22 | 24 | 26 | 19 | 18 | 19 | 15 | 18 | 19 | 15 | 16 | 16 | 13 |
Feels °C | 11 | 18 | 13 | 17 | 24 | 23 | 23 | 24 | 20 | 24 | 25 | 18 | 16 | 16 | 11 | 16 | 16 | 11 | 11 | 11 | 8 |
Swell 1 Height (m) Direction Period (s) | SSE 8 | SSW 10 | SW 21 | SW 18 | SW 16 | SW 15 | SW 14 | SW 13 | WSW 13 | WSW 12 | WSW 12 | WSW 11 | WSW 13 | WSW 13 | WSW 12 | SW 16 | WSW 14 | WSW 14 | WSW 13 | WSW 12 | SW 12 |
290 | 169 | 2326 | 2946 | 1852 | 1343 | 1383 | 1155 | 454 | 294 | 140 | 151 | 304 | 265 | 691 | 4018 | 2878 | 1889 | 1250 | 878 | 558 | |
Swell 2 Height (m) Direction Period (s) | SSW 10 | WSW 10 | SSE 8 | S 8 | SSE 9 | SSE 8 | SSE 6 | — | SSW 12 | SSW 11 | SW 11 | WSW 14 | S 9 | W 11 | SW 17 | — | — | — | — | — | SW 14 |
92 | 38 | 280 | 147 | 101 | 54 | 15 | — | 303 | 156 | 119 | 140 | 13 | 9 | 547 | — | — | — | — | — | 350 | |
Swell 3 Height (m) Direction Period (s) | WSW 10 | SW 25 | SSW 9 | — | — | — | — | — | SW 18 | WSW 16 | S 10 | S 9 | W 11 | — | — | — | — | — | — | — | — |
68 | 163 | 58 | — | — | — | — | — | 13 | 26 | 49 | 27 | 21 | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | SSE 8 | SSE 8 | SSE 8 | — | SSE 8 | — | — | — | — | — | SSW 3 | S 3 | S 4 | S 4 | S 5 | — | S 6 | S 7 | S 7 | SSE 7 | SSE 7 |
532 | 207 | 483 | — | 197 | — | — | — | — | — | 2 | 4 | 10 | 27 | 57 | — | 273 | 532 | 524 | 588 | 270 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 34 | 0 | 0 | 14 | 0 | 3 | 280 | 0 | 0 | 400 | 0 | 130 | 379 | 0 |
Best forecast wave conditions in Cape Town | |||||||||||||||||||||
Best forecast wave conditions in South Africa | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)
Wind Speed (km/h)
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.










