Surf Forecasts:
Nanwan Beach (South Bay) surf forecast from 15 Aug 2026:
- Best quality surf: Saturday 22 Aug, 2AM (local time) - 11ft (3.5m), 10s period, SSW swell with cross-shore winds.
- Most powerful swell: Saturday 22 Aug, 2AM (local time) - 11ft (3.5m), 10s period, SSW swell with 2,654 kJ wave energy.
- Next surfable swell (1★+): Sunday 16 Aug, 8PM (local time) - 7ft (2.1m), 8s period with SW swell.
Best Forecast Surf Conditions for Nanwan Beach (South Bay) this week:
The surf forecast for Nanwan Beach (South Bay) over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Aug 16) at 8PM. The primary swell is predicted to be 2.1m and 8s period with a secondary swell of 0.2m and 11s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Nanwan Beach (South Bay) in the next 16 days are 3.5m 10s and forecast to arrive on Saturday (Aug 22) at 2AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.7m 6s period and expected on Tuesday (Aug 18) at 5PM.
| Wave Type | Time (CST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 8PM (Sun 16th Aug) | 7ft (2.1m) 8s |
| Best Surf | 2AM (Sat 22nd Aug) | 11ft (3.5m) 10s |
| Most Powerful | 2AM (Sat 22nd Aug) | 11ft (3.5m) 10s |
Table - best surf conditions forecast for Nanwan Beach (South Bay) over the next 16 days.
The Lowdown
Righto, grab a seat. This is Rusty, and I'm looking at the coming weeks for Nanwan Beach down in South Bay.
First off, the water temp here is sitting right on 85°, which is pretty standard for this time of year, nothing unusual there.
The outlook for the next 16 days is a bit of a mixed bag, but there are a couple of windows where it might just come together. The biggest issue is the wind, which is going to be a factor for most of the run. We start with a bit of swell on Sunday, the 16th, but with a 16 mph cross-shore wind and some rain, it's going to be a bit of a mess. Not a great start.
Now, the real standout for the whole period looks like Monday morning, the 17th of August. We've got a solid 6 ft swell from the SW, an 8-second period, and the wind is forecast to be glassy – dead calm. That's the kind of morning you set the alarm for. The wave energy is moderate at 534, so there's enough to push you around. The break is a beach and reef setup and it's fairly consistent, so you should get waves. Just a heads-up, the crowds are often here, so you'll have some company, but for clean conditions like that, it's worth it.
After that, the surf drops off fast. From Tuesday, the 18th, through Wednesday, the 19th, the swell gets smaller, around 3 ft to 4 ft, and while the wind is offshore, it's also quite strong. It's not going to be great. There's a long gap of days here with no real recommendations, just small, ordinary conditions.
Things try to pick up again on the weekend of the 22nd and 23rd. On Saturday morning, the 22nd, we see a bigger 10 ft SSW swell with a 10-second period, and the wind is a cross-offshore breeze. That is a powerful one – the combined energy jumps to 1565 – but that size is really only for the experienced crew. The morning looks the best with cleaner conditions, but it's still a bit lumpy.
The following week, from the 24th onwards, is a bit of a weird one. The swell direction swings around to the east with a very long 15 to 16-second period. This is groundswell, and it's pushing a lot of energy, with values like 1064 and 1967. This kind of long-period swell can be tricky at a beach and reef break like this, often closing out or breaking too straight. The wind is mostly onshore or cross-onshore during this period, which isn't ideal, but there's a chance on Wednesday afternoon, the 26th, and Thursday afternoon, the 27th, when the wind goes cross-off or light and the energy is still high. It's a bit of a gamble, but there could be some sneaky clean waves for the dedicated.
To be honest, a lot of this period looks like it could be more appealing for the kite surfers than paddle surfers, given the strong winds and lumpy conditions. There's a lot of poor surf forecasts in there. The best bet is clear: get out there early on Monday, the 17th, for the cleanest waves. The bigger swells later in the month are for the experts only, and the long-period stuff is a wild card.
Rusty.
Short Range ForecastHeavy rain (total 35mm), heaviest during Sun afternoon. Warm (max 30°C on Tue afternoon, min 27°C on Sun afternoon). Winds increasing (calm on Mon morning, fresh winds from the NE by Tue afternoon). | Days 4-6 Weather SummaryHeavy rain (total 61mm), heaviest during Thu afternoon. Warm (max 30°C on Wed morning, min 27°C on Thu morning). Winds increasing (calm on Wed night, strong winds from the SSW by Thu night). | ||||||||||||||||||||
Sunday 16 | Monday 17 | Tuesday 18 | Wednesday 19 | Thursday 20 | Friday 21 | Saturday 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) | SW 8 | SW 8 | SW 9 | SW 8 | SW 9 | SW 8 | SW 8 | SW 8 | SW 8 | SW 9 | SW 8 | SSW 10 | SSW 9 | SW 10 | SSW 10 | SSW 10 | SSW 10 | SSW 10 | SSW 10 | SSW 10 | SSW 10 |
Wave Graph | |||||||||||||||||||||
666 | 792 | 671 | 523 | 429 | 288 | 176 | 176 | 184 | 148 | 166 | 314 | 264 | 573 | 683 | 1501 | 1299 | 2654 | 1561 | 1184 | 873 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross-off | cross-off | glassy | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | on | cross-on | cross-on | cross | cross | cross | cross | cross-off | cross-off | cross |
High Tide | 8:55AM1.03m | 9:26PM0.83m | 9:33AM0.87m | 9:58PM0.88m | 10:10AM0.71m | 10:34PM0.92m | 10:51AM0.58m | 11:17PM0.93m | 12:03PM0.47m | 00:13AM0.94m | 1:28AM0.95m | 2:47AM0.98m | |||||||||
Low Tide | 3:25PM0.26m | 3:20AM0.31m | 3:40PM0.33m | 4:21AM0.35m | 3:48PM0.38m | 5:35AM0.39m | 3:49PM0.42m | 7:25AM0.40m | 3:28PM0.44m | 9:52AM0.36m | 11:01AM0.29m | ||||||||||
5:33 | — | — | 5:35 | — | — | 5:35 | — | — | 5:35 | — | — | 5:35 | — | — | 5:35 | — | — | 5:35 | — | — | |
— | 6:27 | — | — | 6:25 | — | — | 6:24 | — | — | 6:24 | — | — | 6:23 | — | — | 6:22 | — | — | 6:22 | — | |
mm | 13 | 12 | 4 | 3 | — | — | — | 1 | 2 | — | — | 1 | 7 | 18 | 18 | 5 | 5 | 7 | 1 | — | 8 |
Temp °C | 28 | 27 | 28 | 29 | 29 | 28 | 29 | 30 | 29 | 30 | 30 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 29 | 29 | 28 |
Feels °C | 30 | 29 | 32 | 34 | 32 | 30 | 31 | 29 | 28 | 31 | 32 | 30 | 31 | 28 | 27 | 28 | 28 | 31 | 31 | 31 | 31 |
Swell 1 Height (m) Direction Period (s) | NE 11 | NE 11 | SW 9 | SW 8 | SW 9 | SW 8 | SW 8 | SW 8 | SW 8 | SW 9 | SW 8 | SSW 10 | SSW 9 | ENE 9 | SSW 10 | SSW 10 | SSW 10 | ENE 8 | SSW 10 | SSW 10 | SSW 10 |
31 | 30 | 560 | 523 | 429 | 288 | 176 | 176 | 184 | 148 | 166 | 314 | 264 | 124 | 683 | 1072 | 1299 | 6 | 1561 | 1184 | 873 | |
Swell 2 Height (m) Direction Period (s) | ESE 10 | ESE 11 | ENE 10 | ENE 10 | ENE 10 | ENE 10 | ESE 10 | ESE 10 | ESE 10 | ENE 10 | ENE 9 | ENE 8 | ENE 9 | SE 9 | WNW 5 | SSE 10 | SE 9 | — | E 14 | ESE 10 | SE 8 |
11 | 12 | 42 | 40 | 39 | 39 | 11 | 10 | 10 | 19 | 17 | 127 | 141 | 14 | 25 | 61 | 70 | — | 4 | 20 | 15 | |
Swell 3 Height (m) Direction Period (s) | NE 6 | N 6 | ESE 11 | ESE 11 | ESE 11 | ESE 11 | SE 7 | SE 7 | SE 8 | SE 7 | SE 8 | SSE 8 | SE 9 | NW 8 | ENE 9 | NE 8 | ENE 8 | — | — | NE 9 | ESE 10 |
2 | 1 | 12 | 11 | 11 | 11 | 2 | 2 | 2 | 2 | 2 | 7 | 23 | 3 | 62 | 18 | 7 | — | — | 3 | 20 | |
Wind waves Height (m) Direction Period (s) | SW 8 | SW 8 | SW 9 | — | — | NE 4 | NE 5 | ENE 6 | ENE 6 | ENE 7 | ENE 7 | — | SW 4 | SW 10 | — | SSW 10 | — | SSW 10 | — | — | — |
666 | 792 | 671 | — | — | 19 | 80 | 170 | 129 | 153 | 131 | — | 16 | 573 | — | 1501 | — | 2654 | — | — | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 42 | 14 | 0 | 0 | 541 | 329 | 859 | 1195 | 511 | 511 | 0 | 148 | 148 | 316 | 42 | 335 | 316 | 42 | 42 | 14 | 14 |
Best forecast wave conditions in South Taiwan | |||||||||||||||||||||
Best forecast wave conditions in Taiwan | |||||||||||||||||||||
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Information about the Nanwan Beach (South Bay) Surf forecast
The above surf forecast table for Nanwan Beach (South Bay) provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Nanwan Beach (South Bay) can be found by selecting the local surf guide option on the grey menu. Our Nanwan Beach (South 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 (Nanwan Beach (South 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 Nanwan Beach (South 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.











