
Surf Forecasts:
Big Bay surf forecast from 12 Aug 2026:
- Best quality surf: Thursday 13 Aug, 5AM (local time) - 5ft (1.6m), 20s period, SW swell with offshore winds.
- Most powerful swell: Thursday 13 Aug, 11AM (local time) - 7ft (2.2m), 17s period, WSW swell with 2,998 kJ wave energy.
- Next surfable swell (1★+): Wednesday 12 Aug, 5PM (local time) - 6ft (1.8m), 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 Wednesday (Aug 12) at 5PM. The primary swell is predicted to be 1.8m and 18s period with a secondary swell of 0.8m and 10s. 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 2.2m 17s and forecast to arrive on Thursday (Aug 13) at 11AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.1m 5s period and expected on Monday (Aug 17) at 5PM.
| Wave Type | Time (SAST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 5PM (Wed 12th Aug) | 6ft (1.8m) 18s |
| Best Surf | 5AM (Thu 13th Aug) | 5ft (1.6m) 20s |
| Most Powerful | 11AM (Thu 13th Aug) | 7ft (2.2m) 17s |
Table - best surf conditions forecast for Big Bay over the next 16 days.
The Lowdown
Alright, Rusty here again. Let’s talk about Big Bay in feet and miles per hour.
Water temp is a chilly 55°F, which is way colder than normal for this time of year. You’ll want a thick suit and maybe booties.
Wednesday 12 August kicks things off with a clean 6 ft swell from the SW at an 18-second period. That’s long-period groundswell with some serious energy (2215 combined). Wind is a light cross-offshore at 9 mph from the ENE, so the surface is clean. This is a strong, experienced surfer’s wave. Afternoon improves with a pure offshore ESE breeze and swell holding at 6 ft. This is a standout early session: clean, powerful, and long.
Thursday 13 August gets messy. The swell jumps to 7 ft from the WSW in the morning but the wind goes cross-shore from the NNE at 9 mph. Afternoon brings onshore wind from the NW at 6 mph. Not the best.
Friday 14 August is lumpy. 6 ft swell but cross-onshore winds spoil the surface. The energy drops. Surfable but not great.
Saturday 15 August – this is the highlight of the first week. Morning is absolutely glassy, dead calm, with a 6 ft SW swell at a 13-second period. The energy is solid (1152). The wind stays light and cross-offshore from the south in the afternoon. This is going to be clean, lined up, and fun all day.
Sunday 16 August is a bit bumpy with cross-on winds, but the swell holds at 6 to 6 ft.
Monday 17 August brings a big pulse: 8 ft from the WSW in the morning. That’s expert-only territory. Clean with a cross-off wind, the combined energy is huge (2245). Afternoon drops to 7 ft but stays clean. A second standout for strong surfers.
Tuesday 18 August starts glassy with a 7 ft SW swell. Glassy and solid. This is an absolute gem. The afternoon goes a little cross-shore so morning is the call.
The end of the first week and start of the second week fade out. By Thursday 20 August the swell is down to 4 ft with onshore wind. Friday 21 August is tiny – 3 to 3 ft – and the energy is weak (289).
But Saturday 22 August shows a bump: 5 ft from the SW with clean conditions. Sunday 23 August is a proper standout for the second week: 6 ft in the morning with offshore wind from the east. Clean and punchy, energy at 1182. Worth the trip.
Monday 24 August is blown out with 22 mph onshore winds and tiny waves. No good.
Tuesday 25 August has a weird one: only 2 ft of swell but a 19-second period, and glassy conditions. That’ll produce long, slow lines – fun for a longboard.
Wednesday 26 August is clean at 5 ft. Thursday 27 August is the final standout: morning is dead calm and glassy with a 6 ft WSW swell, 12-second period, and energy over 1000 (1068). Clean, punchy, and well-shaped. Afternoon picks up to 7 ft but gets a light cross-shore wind.
Best of the best: Saturday 15 August and Tuesday 18 August in the first week. Sunday 23 August and Thursday 27 August in the second. Solid run overall.
Rusty.
Short Range ForecastMostly dry. Warm (max 27°C on Thu afternoon, min 13°C on Wed morning). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Very mild (max 19°C on Sat afternoon, min 13°C on Sun morning). Wind will be generally light. | ||||||||||||||||||||
Wednesday 12 | Thursday 13 | Friday 14 | Saturday 15 | Sunday 16 | Monday 17 | Tuesday 18 | |||||||||||||||
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 18 | WSW 16 | WSW 17 | WSW 16 | WSW 16 | WSW 15 | WSW 14 | WSW 14 | WSW 13 | WSW 14 | WSW 14 | WSW 14 | WSW 14 | WSW 13 | WSW 13 | WSW 13 | WSW 13 | WSW 12 | WSW 12 | SW 12 |
Wave Graph | |||||||||||||||||||||
1922 | 1952 | 1809 | 2998 | 2262 | 1663 | 1358 | 1257 | 1059 | 1144 | 1179 | 1161 | 1207 | 1484 | 2313 | 2245 | 1725 | 1504 | 1163 | 936 | 383 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | off | cross-off | cross | on | cross-off | cross-on | cross-on | glassy | glassy | cross-off | on | cross-on | cross-on | cross-off | cross-off | cross-off | cross-off | glassy | cross | cross-off |
High Tide | 3:13PM1.62m | 3:29AM1.57m | 3:52PM1.68m | 4:09AM1.56m | 4:29PM1.69m | 4:46AM1.51m | 5:05PM1.64m | 5:22AM1.43m | 5:39PM1.55m | 5:57AM1.33m | 6:13PM1.43m | 6:32AM1.21m | 6:48PM1.29m | ||||||||
Low Tide | 9:01AM0.02m | 9:27PM0.05m | 9:40AM-0.01m | 10:07PM0.02m | 10:16AM-0.00m | 10:45PM0.03m | 10:51AM0.05m | 11:22PM0.09m | 11:24AM0.14m | 11:57PM0.19m | 11:57AM0.25m | 00:31AM0.30m | 12:30PM0.38m | 1:08AM0.42m | |||||||
7:28 | — | — | 7:26 | — | — | 7:26 | — | — | 7:24 | — | — | 7:24 | — | — | 7:22 | — | — | 7:22 | — | — | |
— | 6:14 | — | — | 6:14 | — | — | 6:15 | — | — | 6:15 | — | — | 6:15 | — | — | 6:16 | — | — | 6:17 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 16 | 21 | 20 | 22 | 27 | 21 | 17 | 16 | 15 | 16 | 19 | 18 | 16 | 17 | 15 | 16 | 18 | 15 | 15 | 16 | 14 |
Feels °C | 12 | 18 | 16 | 19 | 22 | 18 | 14 | 14 | 15 | 15 | 17 | 17 | 14 | 15 | 15 | 15 | 16 | 14 | 15 | 14 | 12 |
Swell 1 Height (m) Direction Period (s) | SW 18 | SW 18 | WSW 16 | WSW 17 | WSW 16 | WSW 16 | WSW 15 | WSW 14 | WSW 14 | WSW 13 | WSW 14 | WSW 14 | WSW 14 | WSW 14 | WSW 13 | WSW 13 | WSW 13 | WSW 13 | WSW 12 | WSW 12 | WSW 11 |
1922 | 1952 | 1809 | 2998 | 2262 | 1663 | 1358 | 1257 | 1059 | 1144 | 1179 | 1161 | 1207 | 1484 | 2313 | 2245 | 1725 | 1504 | 1163 | 936 | 383 | |
Swell 2 Height (m) Direction Period (s) | SSW 10 | SSW 10 | SW 21 | NNW 7 | — | — | — | NW 5 | W 5 | W 5 | — | — | — | — | — | — | — | SW 13 | SW 12 | — | SW 12 |
187 | 116 | 898 | 18 | — | — | — | 11 | 13 | 8 | — | — | — | — | — | — | — | 205 | 416 | — | 349 | |
Swell 3 Height (m) Direction Period (s) | SW 10 | SW 10 | S 10 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | SSE 5 | SSE 5 | — | — |
106 | 65 | 9 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 26 | 3 | — | — | |
Wind waves Height (m) Direction Period (s) | — | — | ESE 3 | — | NNW 5 | — | NW 4 | — | — | — | — | — | — | — | — | — | S 5 | — | — | — | — |
— | — | 9 | — | 33 | — | 16 | — | — | — | — | — | — | — | — | — | 52 | — | — | — | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 0 | 2 | 2 | 29 | 0 | 2 | 0 | 0 | 0 | 0 | 29 | 4 | 29 | 0 | 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.











