Surf Forecasts:
Nanwan Beach (South Bay) surf forecast from 21 Aug 2026:
- Best quality surf: Thursday 27 Aug, 5AM (local time) - 7ft (2.1m), 9s period, SW swell with glassy winds.
- Most powerful swell: Tuesday 25 Aug, 2PM (local time) - 7.5ft (2.3m), 18s period, E swell with 3,231 kJ wave energy.
- Next surfable swell (1★+): Thursday 27 Aug, 2AM (local time) - 6ft (1.9m), 9s 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 Thursday (Aug 27) at 2AM. The primary swell is predicted to be 1.9m and 9s period with a secondary swell of 0.2m and 8s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Nanwan Beach (South Bay) in the next 16 days are 2.3m 18s and forecast to arrive on Tuesday (Aug 25) at 2PM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 2.4m 17s period and expected on Tuesday (Aug 25) at 8PM.
| Wave Type | Time (CST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 2AM (Thu 27th Aug) | 6ft (1.9m) 9s |
| Best Surf | 5AM (Thu 27th Aug) | 7ft (2.1m) 9s |
| Most Powerful | 2PM (Tue 25th Aug) | 7.5ft (2.3m) 18s |
Table - best surf conditions forecast for Nanwan Beach (South Bay) over the next 16 days.
The Lowdown
Alright, let’s get into it.
The next couple of weeks are going to be a mixed bag at Nanwan Beach (South Bay). There’s plenty of swell around, but the winds are going to make life tricky early on. We’ve got a solid window opening up, but you’re going to have to be patient and pick your sessions carefully. There’s a real standout right at the end if you can wait it out.
Right out of the gate, Friday afternoon (August 21st) is a wash. There’s a lumpy 12ft SW swell with a strong cross-shore wind and thunderstorms. It’s a mess out there. The energy is seriously strong (2173), but it’s just not clean. This setup looks more interesting for kite surfing than paddle surfing. Saturday (August 22nd) is better, but still not great. The swell drops to 10ft and the wind goes a bit cross-offshore, making it cleaner, but the scores are still marginal. Not worth getting too excited about.
Sunday (August 23rd) is poor. The wind is up again, with 22-25 mph cross-shore winds and messy surf. Monday (August 24th) morning is a bit cleaner, but the afternoon is blown out again with a bigger 13ft SW swell. This is pushing it for size and the conditions are just rough.
Tuesday (August 25th) is a strange one. The swell direction swings around to the east, coming in at 7-8ft, but the period jumps way up to 17-18 seconds. That’s some serious long-period groundswell, but the cross-shore wind is lumping it up. It’s a big energy event (3806-4071), but the quality isn’t there. Wednesday (August 26th) and Thursday morning (August 27th) are poor to marginal with the swell dropping off.
Now, Thursday afternoon (August 27th) is our first real glimmer of hope. The wind drops to nothing, going glassy, and we’ve got a clean 8ft SW swell on a 10-second period. The wave comment says to expect very good surf conditions. This is the one to circle.
Friday (August 28th) and Saturday (August 29th) are back to marginal. The wind is light and cross-shore, but it’s not glassy. Sunday morning (August 30th) is another one to watch. We get that glassy wind again, with a clean 7ft SW swell. Then Monday afternoon (August 31st) is looking great. The wind is glassy out of the north, and the swell has picked up to 8ft at 12 seconds. This is excellent surf for experienced surfers. Tuesday (September 1st) is the next run of great conditions. We’ve got glassy conditions in the morning with a 7ft SW swell, and the cross-offshore wind in the afternoon. This is looking like a great couple of days.
The middle of the week (Sept 2nd and 3rd) is marginal again, but the energy is still there. Then, we get to the real highlight. Friday afternoon (September 4th) and all day Saturday (September 5th) are the best on offer. The swell is still a fun 6-6ft, but it’s coming from the east with a longer period (12-14 seconds). The wind is offshore or cross-offshore and it’s clean. The energy for Saturday afternoon is strong at 1911. This is the true standout of the forecast, but it’s still over a week away, so treat it as promising rather than guaranteed.
The water temps are sitting right at 84°, which is about average for this time of year.
Good luck out there.
Rusty
Short Range ForecastHeavy rain (total 208mm), heaviest during Sun afternoon. Warm (max 28°C on Fri night, min 26°C on Sun morning). Winds increasing (moderate winds from the WSW on Sat night, strong winds from the WSW by Sun afternoon). | Days 5-7 Weather SummaryHeavy rain (total 102mm), heaviest during Wed night. Warm (max 28°C on Mon afternoon, min 27°C on Wed night). Winds decreasing (strong winds from the WSW on Mon afternoon, calm by Wed night). | |||||||||||||||||||
Fri 21 | Saturday 22 | Sunday 23 | Monday 24 | Tuesday 25 | Wednesday 26 | Thursday 27 | ||||||||||||||
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 10 | SW 10 | SW 10 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | E 18 | E 18 | E 17 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 10 | SW 9 |
Wave Graph | ||||||||||||||||||||
2173 | 1790 | 1564 | 1360 | 1162 | 1274 | 1382 | 1032 | 1248 | 2387 | 1204 | 2796 | 3016 | 684 | 515 | 564 | 606 | 690 | 948 | 944 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross | cross-off | cross-off | cross | cross | cross | cross | cross-off | cross | cross | cross | cross | cross | cross | cross | glassy | cross | glassy | cross |
High Tide | 1:28AM0.95m | 2:47AM0.98m | 3:51AM1.03m | 6:41PM0.54m | 4:42AM1.09m | 6:38PM0.56m | 5:24AM1.14m | 6:49PM0.59m | 6:02AM1.17m | 7:06PM0.64m | ||||||||||
Low Tide | 11:01AM0.29m | 11:37AM0.24m | 12:05PM0.19m | 9:07PM0.52m | 12:31PM0.16m | 10:17PM0.46m | 12:55PM0.14m | 11:07PM0.40m | 1:18PM0.14m | 11:51PM0.35m | ||||||||||
— | — | 5:35 | — | — | 5:37 | — | — | 5:37 | — | — | 5:37 | — | — | 5:37 | — | — | 5:37 | — | — | |
6:22 | — | — | 6:22 | — | — | 6:21 | — | — | 6:21 | — | — | 6:20 | — | — | 6:19 | — | — | 6:17 | — | |
mm | 26 | 35 | 12 | 7 | 21 | 20 | 42 | 33 | 12 | 6 | 14 | 9 | 6 | 11 | 5 | 9 | 27 | 15 | 12 | 1 |
Temp °C | 27 | 28 | 27 | 27 | 27 | 27 | 27 | 27 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 27 | 28 | 28 |
Feels °C | 26 | 28 | 29 | 28 | 29 | 26 | 25 | 27 | 30 | 27 | 27 | 29 | 28 | 29 | 30 | 30 | 33 | 32 | 34 | 31 |
Swell 1 Height (m) Direction Period (s) | ENE 8 | NE 9 | ESE 10 | ESE 10 | ESE 10 | ESE 10 | E 14 | SE 8 | ESE 8 | E 21 | E 18 | E 18 | SW 9 | ENE 16 | SW 9 | SW 9 | ENE 12 | SW 9 | NE 12 | NNE 12 |
7 | 3 | 10 | 20 | 20 | 19 | 4 | 32 | 26 | 133 | 1204 | 2796 | 1055 | 2394 | 515 | 564 | 241 | 690 | 114 | 56 | |
Swell 2 Height (m) Direction Period (s) | — | — | NE 8 | NE 8 | NE 9 | NE 9 | E 14 | E 14 | ESE 14 | ESE 13 | E 12 | ENE 11 | E 17 | SW 9 | ENE 14 | ENE 14 | SSE 8 | NE 12 | ENE 13 | ENE 13 |
— | — | 3 | 3 | 3 | 3 | 16 | 15 | 69 | 60 | 77 | 11 | 3016 | 684 | 1187 | 955 | 6 | 175 | 35 | 34 | |
Swell 3 Height (m) Direction Period (s) | — | — | — | E 10 | — | — | NE 7 | NE 6 | NE 7 | SE 8 | E 10 | — | ENE 11 | NE 9 | NE 8 | SSE 8 | ESE 10 | ENE 14 | E 11 | SE 10 |
— | — | — | 2 | — | — | 2 | 2 | 2 | 16 | 7 | — | 12 | 217 | 70 | 7 | 11 | 40 | 9 | 4 | |
Wind waves Height (m) Direction Period (s) | SW 10 | SW 10 | SW 10 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | — | — | — | — | SW 9 | — | SW 10 | SW 9 |
2173 | 1790 | 1564 | 1360 | 1162 | 1274 | 1382 | 1032 | 1248 | 2387 | 1112 | 1010 | — | — | — | — | 606 | — | 948 | 944 | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 348 | 348 | 335 | 14 | 42 | 148 | 348 | 148 | 535 | 148 | 148 | 442 | 442 | 42 | 42 | 14 | 0 | 2 | 0 | 79 |
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.











