Surf Forecasts:
Nanwan Beach (South Bay) surf forecast from 11 Aug 2026:
- Best quality surf: Sunday 16 Aug, 8PM (local time) - 7ft (2.1m), 9s period, SW swell with cross-offshore winds.
- Most powerful swell: Saturday 15 Aug, 5PM (local time) - 8ft (2.5m), 9s period, SW swell with 1,011 kJ wave energy.
- Next surfable swell (1★+): Sunday 16 Aug, 8PM (local time) - 7ft (2.1m), 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 Sunday (Aug 16) at 8PM. The primary swell is predicted to be 2.1m and 9s period. 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 2.5m 9s and forecast to arrive on Saturday (Aug 15) at 5PM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.7m 13s period and expected on Tuesday (Aug 11) at 11AM.
| Wave Type | Time (CST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 8PM (Sun 16th Aug) | 7ft (2.1m) 9s |
| Best Surf | 8PM (Sun 16th Aug) | 7ft (2.1m) 9s |
| Most Powerful | 5PM (Sat 15th Aug) | 8ft (2.5m) 9s |
Table - best surf conditions forecast for Nanwan Beach (South Bay) over the next 16 days.
The Lowdown
Alright, let’s break it down for Nanwan Beach (South Bay) — a beach and reef setup that’s fairly consistent and takes swell from the southeast best. Water temp is about 85°, which is normal for the season.
The first few days are a write-off. Tuesday the 11th and Wednesday the 12th have SW swell running 7 to 8 feet, with thunderstorms and cross to cross-off winds at 15 to 19 mph. The energy is strong, around 864 to 993, but the surf is just poor — lumpy and choppy. Thursday the 13th and Friday the 14th are similar, with swell a bit smaller at 6 to 7 feet, still messy.
Saturday the 15th morning shows some promise — 8 feet of SW swell, 9 seconds, cross-off wind at 12 mph, energy at 776. Still labeled marginal, but the surface is clean. Sunday the 16th is the same story: 8 feet, cross-off, clean, with energy spiking to 1579. Not a classic, but the best of the first week.
Monday the 17th and Tuesday the 18th bring a drop in size to 5 feet, but the wind goes light, cross-off, and conditions are clean. The energy is around 291 to 297, so it’s small but clean. Fun for the intermediates.
Then it goes flat from Wednesday the 19th through Saturday the 22nd. Swell down to 4 feet, wind gets strong and cross, energy weak. The only bright spot is Thursday the 20th afternoon when the wind goes glassy — 4 feet from the SSW, 9 seconds, 218 energy, but it’s just ordinary.
Sunday the 23rd afternoon is the standout. Swell jumps to 8 feet from the SSW, 9 seconds, energy at 1644. Wind is light from the NNE, cross-off, and conditions are clean. This is excellent surf for experienced surfers — powerful, clean, and the best of the whole forecast.
Monday the 24th is messy again, but Tuesday the 25th afternoon brings a huge shift: the swell goes to the ESE, 15 seconds — that’s a very long period groundswell — and energy hits 5003. The swell is 12 feet, and the wind is cross-off. But it’s too big for this break. Wednesday the 26th is even bigger, with 25 feet of swell, 16 seconds, energy at 28824 — again, too big for most. Those are expert-only days.
So, the standout is Sunday the 23rd afternoon. That’s your clean, powerful, 8-foot day. The long-range stuff on the 25th and 26th is massive and dangerous. Everything else is a mix of chop and small clean waves. Patience is key.
Rusty.
Short Range ForecastHeavy rain (total 42mm), heaviest during Tue afternoon. Warm (max 29°C on Tue afternoon, min 28°C on Tue morning). Mainly fresh winds. | Days 4-6 Weather SummaryHeavy rain (total 70mm), heaviest during Sat night. Warm (max 29°C on Fri morning, min 28°C on Fri morning). Wind will be generally light. | ||||||||||||||||||||
Tuesday 11 | Wednesday 12 | Thursday 13 | Friday 14 | Saturday 15 | Sunday 16 | Monday 17 | |||||||||||||||
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 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 8 | SW 8 | SW 8 | SW 8 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 |
Wave Graph  | |||||||||||||||||||||
 kJ | 947 | 823 | 818 | 727 | 675 | 580 | 595 | 505 | 523 | 479 | 663 | 787 | 769 | 1011 | 808 | 853 | 770 | 612 | 550 | 503 | 357 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross | cross-off | cross | cross | cross-off | cross | cross | cross-off | cross-off | cross-off | cross-off | off | cross-off |
High Tide | 7:05PM0.54m | 5:59AM1.35m | 7:32PM0.57m | 6:48AM1.35m | 7:59PM0.62m | 7:33AM1.28m | 8:26PM0.69m | 8:15AM1.17m | 8:55PM0.76m | 8:55AM1.03m | 9:26PM0.83m | 9:33AM0.87m | 9:58PM0.88m | ||||||||
Low Tide | 12:56PM-0.02m | 10:47PM0.40m | 1:35PM-0.01m | 11:46PM0.34m | 2:10PM0.03m | 00:41AM0.30m | 2:39PM0.10m | 1:33AM0.28m | 3:05PM0.18m | 2:26AM0.28m | 3:25PM0.26m | 3:20AM0.31m | 3:40PM0.33m | 4:21AM0.35m | |||||||
 | |  | | | | | | | | | | | | | |  | |  | | | |
 | 5:33 | — | — | 5:33 | — | — | 5:33 | — | — | 5:33 | — | — | 5:33 | — | — | 5:33 | — | — | 5:35 | — | — |
 | — | 6:30 | — | — | 6:30 | — | — | 6:29 | — | — | 6:28 | — | — | 6:28 | — | — | 6:27 | — | — | 6:25 | — |
mm | 6 | 5 | 6 | 4 | 2 | 5 | 3 | 2 | 9 | 5 | 5 | 13 | 8 | 7 | 18 | 8 | 3 | 3 | — | 2 | 2 |
Temp °C | 28 | 29 | 28 | 29 | 29 | 28 | 29 | 29 | 28 | 29 | 29 | 28 | 29 | 29 | 28 | 28 | 29 | 28 | 29 | 29 | 29 |
Feels °C | 29 | 30 | 31 | 30 | 30 | 30 | 30 | 30 | 29 | 31 | 30 | 30 | 31 | 30 | 31 | 30 | 31 | 32 | 32 | 32 | 33 |
Swell 1 Height (m) Direction Period (s) | ENE 13 | ENE 13 | ENE 12 | ENE 12 | SW 9 | ENE 12 | ENE 11 | ENE 11 | ENE 10 | SW 8 | NE 10 | ENE 10 | SW 9 | ENE 10 | SSE 8 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 | SW 9 |
| kJ | 181 | 178 | 117 | 113 | 675 | 78 | 47 | 46 | 41 | 479 | 25 | 20 | 769 | 10 | 6 | 711 | 635 | 612 | 550 | 503 | 357 |
Swell 2 Height (m) Direction Period (s) | SE 10 | SE 9 | SE 8 | SE 8 | ENE 12 | SE 8 | SE 8 | SE 8 | SE 8 | NE 10 | SE 8 | SE 8 | ENE 10 | ESE 10 | ENE 11 | ENE 11 | NE 11 | NE 10 | ENE 10 | ENE 10 | ENE 10 |
| kJ | 46 | 41 | 35 | 35 | 78 | 17 | 16 | 11 | 9 | 26 | 11 | 11 | 10 | 11 | 12 | 24 | 31 | 28 | 40 | 39 | 38 |
Swell 3 Height (m) Direction Period (s) | N 10 | N 10 | NE 9 | — | SE 8 | N 8 | NE 8 | N 8 | NE 8 | SE 9 | NNE 8 | SE 11 | SSE 8 | ESE 10 | ESE 10 | SE 10 | SSE 8 | ESE 11 | ESE 11 | ESE 11 | ESE 11 |
| kJ | 2 | 2 | 3 | — | 34 | 1 | 3 | 1 | 3 | 12 | 6 | 5 | 7 | 11 | 10 | 15 | 6 | 12 | 11 | 11 | 11 |
Wind waves Height (m) Direction Period (s) | SW 9 | SW 9 | SW 9 | SW 9 | — | SW 9 | SW 9 | SW 8 | SW 8 | — | SW 8 | SW 9 | — | SW 9 | SW 9 | SW 9 | SW 9 | — | — | — | — |
| kJ | 947 | 823 | 818 | 727 | — | 580 | 595 | 505 | 523 | — | 663 | 787 | — | 1011 | 808 | 853 | 770 | — | — | — | — |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 363 | 378 | 148 | 42 | 42 | 316 | 363 | 316 | 348 | 378 | 329 | 348 | 535 | 14 | 14 | 42 | 14 | 14 | 0 | 0 | 0 |
Best forecast wave conditions in South Taiwan | |||||||||||||||||||||
Best forecast wave conditions in Taiwan | |||||||||||||||||||||
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)
Latest Updates
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Nanwan Beach (South Bay) surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
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.
Nearest