Surf Forecasts:
Big Bay surf forecast from 31 Aug 2026:
- Best quality surf: Tuesday 1 Sep, 11PM (local time) - 10ft (3.0m), 13s period, SW swell with cross-offshore winds.
- Most powerful swell: Wednesday 2 Sep, 2AM (local time) - 10ft (3.0m), 14s period, SW swell with 3,688 kJ wave energy.
- Next surfable swell (1★+): Monday 31 Aug, 8PM (local time) - 5ft (1.5m), 11s 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 Monday (Aug 31) at 8PM. The primary swell is predicted to be 1.5m and 11s period with a secondary swell of 1.3m and 11s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Big Bay in the next 16 days are 3.0m 14s and forecast to arrive on Wednesday (Sep 02) at 2AM. Winds are predicted to be offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.5m 3s period and expected on Monday (Aug 31) at 5PM.
| Wave Type | Time (SAST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 8PM (Mon 31st Aug) | 5ft (1.5m) 11s |
| Best Surf | 11PM (Tue 1st Sep) | 10ft (3.0m) 13s |
| Most Powerful | 2AM (Wed 2nd Sep) | 10ft (3.0m) 14s |
Table - best surf conditions forecast for Big Bay over the next 16 days.
The Lowdown
Alright, Rusty here. Let's talk about the waves coming our way at Big Bay.
We've got a solid run of swell on the horizon, but you've gotta pick your moments. The water's sitting at 55.2° right now, which is about 4.9° colder than what we'd normally expect for this time of year. That's a big anomaly, so don't be surprised if that chill hits you harder than usual when you first get in. It's a winter hangover, for sure.
The real standout is shaping up for Wednesday, September 2nd, in the morning. We're looking at a clean 9.8ft swell pushing in from the southwest, with a long 13-second period between waves. That's proper groundswell, packing a heap of punch with a combined energy of 3169. The wind is light from the south, coming cross-offshore, which is going to leave the face of those waves looking like glass. This is proper big-wave territory though – at 9.8ft, it's strictly for the experienced crew. Beginners need to sit this one out and watch from the sand.
Thursday, September 3rd, is also a big one. The morning shows a solid 11.5ft southwest swell, but the wind is gusting to 16 mph from the south. It's still cross-off, so the waves will be clean, but that wind is going to make paddling out a battle. The combined energy hits a massive 5314, which is serious power. The afternoon, however, turns into a write-off with a 31 mph southerly gale. That's a hard pass.
The following weekend, Saturday, September 5th, is worth a look if you're after something a bit more manageable. The swell drops to 6.2ft, coming from the SSE, but the period is a short 7 seconds. It's a bit of a weaker, windswell-type wave, but the morning wind is offshore from the southeast, so it'll be clean. The combined energy is 681, so it's not a heavyweight, but it's fun, and it's a good option for a wider range of surfers.
Looking further out, the morning of Sunday, September 6th, has some serious potential. It's a 4.3ft swell, but the period is a very long 15 seconds, coming from the southwest. Combined energy is 1154, and the wind is a moderate offshore breeze from the east. That long period will mean those waves are packing a ton of energy and will hold up well, but at a place like Big Bay, that long period groundswell can make it a bit tricky, breaking a little too straight in sections. Still, a clean, offshore day with that much power is a standout for the experienced surfer.
The second week starts to fade. We get a few small, clean days on the 7th, but by the 8th of September, it drops to knee-high mush. There's a gap of a few days of very small surf, but then it looks like it might pick up again around Saturday, September 12th. The morning of the 12th is promising, with a clean 6.2ft swell from the WSW and a 13-second period, and a light cross-offshore wind. Combined energy is 1251. The same look holds for the morning of Sunday, the 13th. That's a promising call for the second week, but it's a long way out, so don't book your flights just yet.
Overall, if you're an expert, Wednesday morning, September 2nd is the best bet on offer. For the slightly less intense but still clean option, the morning of Saturday, September 5th is your best bet. Don't bother with the afternoons on the big days as the wind ruins it.
Short Range ForecastMostly dry. Very mild (max 17°C on Wed afternoon, min 11°C on Mon night). Wind will be generally light. | Days 5-7 Weather SummarySome drizzle, heaviest during Thu afternoon. Warm (max 23°C on Sat afternoon, min 11°C on Sat morning). Winds decreasing (near gales from the SSE on Thu afternoon, light winds from the SSE by Sat afternoon). | |||||||||||||||||||
Mon 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | Friday 4 | Saturday 5 | Sunday 6 | ||||||||||||||
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 11 | SW 11 | SW 13 | SW 13 | SW 14 | SW 13 | SW 13 | WSW 13 | S 9 | S 9 | S 9 | S 9 | SSE 8 | S 8 | SE 7 | SSE 7 | SW 17 | SW 15 | SW 15 | SW 14 |
Wave Graph | ||||||||||||||||||||
821 | 1237 | 2429 | 3208 | 3688 | 3169 | 2682 | 1700 | 1291 | 1172 | 847 | 854 | 671 | 264 | 261 | 193 | 648 | 606 | 649 | 422 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross-off | glassy | cross-on | off | cross | cross | cross-off | cross | cross-off | cross-off | off | cross-off | off | off | cross-off | off | off | off | off |
High Tide | 5:03PM1.59m | 5:23AM1.41m | 5:38PM1.52m | 6:02AM1.31m | 6:19PM1.41m | 6:49AM1.20m | 7:11PM1.27m | 7:57AM1.08m | 8:31PM1.15m | 9:47AM1.03m | 10:28PM1.12m | 11:37AM1.12m | 00:03AM1.20m | |||||||
Low Tide | 11:18PM0.11m | 11:22AM0.18m | 11:55PM0.19m | 11:59AM0.28m | 00:39AM0.29m | 12:46PM0.40m | 1:38AM0.41m | 1:56PM0.53m | 3:14AM0.50m | 3:58PM0.59m | 5:14AM0.47m | 5:54PM0.50m | ||||||||
— | — | 7:05 | — | — | 7:03 | — | — | 7:01 | — | — | 7:01 | — | — | 6:58 | — | — | 6:58 | — | — | |
6:27 | — | — | 6:27 | — | — | 6:28 | — | — | 6:29 | — | — | 6:29 | — | — | 6:30 | — | — | 6:30 | — | |
mm | — | — | — | — | — | — | — | — | — | 1 | — | — | — | — | — | — | — | — | — | — |
Temp °C | 14 | 12 | 13 | 14 | 13 | 16 | 17 | 14 | 15 | 15 | 15 | 17 | 19 | 14 | 18 | 23 | 19 | 20 | 22 | 17 |
Feels °C | 10 | 10 | 12 | 11 | 11 | 15 | 14 | 13 | 12 | 5 | 7 | 10 | 11 | 9 | 14 | 21 | 16 | 18 | 20 | 15 |
Swell 1 Height (m) Direction Period (s) | SW 11 | SW 11 | SW 13 | SW 13 | SW 14 | SW 13 | SW 13 | WSW 13 | WSW 12 | WSW 12 | WSW 12 | WSW 11 | WSW 11 | WSW 10 | SSE 7 | SSW 10 | SW 17 | SW 15 | SW 15 | SW 14 |
821 | 1237 | 2429 | 3208 | 3688 | 3169 | 2682 | 1700 | 934 | 754 | 392 | 143 | 93 | 69 | 140 | 63 | 648 | 606 | 649 | 422 | |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | — | — | S 9 | SSW 10 | — | — | S 14 | SW 10 | SSW 13 | SSW 10 | WSW 10 | S 9 | SSE 8 | SSE 9 | SSE 9 |
— | — | — | — | — | — | — | 110 | 328 | — | — | 4 | 59 | 17 | 75 | 39 | 106 | 120 | 99 | 92 | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | W 15 | — | — | — | — | SW 11 | WSW 10 | S 9 | SW 10 | SSW 17 | — | — |
— | — | — | — | — | — | — | — | 69 | — | — | — | — | 5 | 58 | 38 | 24 | 188 | — | — | |
Wind waves Height (m) Direction Period (s) | S 3 | — | — | — | — | — | — | — | S 9 | S 9 | S 9 | S 9 | SSE 8 | S 8 | SE 7 | SSE 7 | SSE 7 | — | SSE 8 | — |
5 | — | — | — | — | — | — | — | 1291 | 1172 | 847 | 854 | 671 | 264 | 261 | 193 | 139 | — | 187 | — | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 39 | 0 | 0 | 13 | 34 | 0 | 0 | 14 | 2 | 165 | 3870 | 1072 | 1277 | 1976 | 0 | 0 | 0 | 0 | 0 | 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.











