Surf Forecasts:
Viana do Castelo surf forecast from 29 Aug 2026:
- Best quality surf: Monday 31 Aug, 7AM (local time) - 5ft (1.6m), 10s period, NW swell with cross-offshore winds.
- Most powerful swell: Monday 31 Aug, 10AM (local time) - 5.5ft (1.7m), 10s period, NW swell with 569 kJ wave energy.
- Next surfable swell (1★+): Sunday 30 Aug, 1AM (local time) - 5ft (1.5m), 8s period with WNW swell.
Best Forecast Surf Conditions for Viana do Castelo this week:
The surf forecast for Viana do Castelo over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Aug 30) at 1AM. The primary swell is predicted to be 1.5m and 8s period with a secondary swell of 0.1m and 10s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Viana do Castelo in the next 16 days are 1.7m 10s and forecast to arrive on Monday (Aug 31) at 10AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.0m 5s period and expected on Tuesday (Sep 01) at 10PM.
| Wave Type | Time (WEST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 1AM (Sun 30th Aug) | 5ft (1.5m) 8s |
| Best Surf | 7AM (Mon 31st Aug) | 5ft (1.6m) 10s |
| Most Powerful | 10AM (Mon 31st Aug) | 5.5ft (1.7m) 10s |
Table - best surf conditions forecast for Viana do Castelo over the next 16 days.
The Lowdown
Alright, Rusty here. Let’s take a look at what’s on the menu for the next couple of weeks along this stretch.
We’re kicking off at Viana do Castelo (a river break), and we’ve got a bit of a slow start. Saturday the 29th is pretty much a write-off – small, messy, and not worth paddling out for. The water temp is sitting about average for this time of year, nothing to write home about.
The real action starts to spark up on Sunday morning the 30th. We’ve got a clean 5ft NW swell rolling in with a light NNW breeze – cross-off, so the faces will be looking tidy. The combined energy is moderate (397), and it’s a decent beginner-friendly size. There’ll be some fun ones, but keep an eye on the crowds, this place can get busy.
Monday the 31st is where it starts to get interesting. The morning session is the pick of the early week: 6ft NW groundswell with a 10-second period, clean conditions thanks to a light N cross-off breeze. The wave energy is moderate to strong (569). Still not huge, but the quality is there for a good session without it being too heavy.
We hit a bit of a lull mid-week from Tuesday afternoon through the end of the first week. Swell drops off, winds pick up, and it gets ordinary. By Thursday the 3rd we’re scraping around 3ft to 4ft with choppy sideshore conditions – not worth the drive.
But then Saturday the 5th throws a curveball. Morning brings a glassy, 3ft NW swell – but the period? 13 seconds. That’s a long-period groundswell. Combined energy jumps to moderate (308). For such a small wave height, that’s a lot of push. This is one for the reef or river-mouth connoisseur – it may stand up nicely on the better banks. It’s a sneaky standout if you know where to sit.
Sunday the 6th keeps the glassy theme in the morning, with a 4ft NW swell at 11 seconds. Clean, lined-up, and user-friendly. Another solid option.
The middle of the second week gets lumpy again, with stronger winds and messy conditions from the 8th to the 10th. Swell drops right off, and confidence fades.
Now – the big one. Saturday the 12th morning is pure magic. Clean 5ft WSW groundswell with a 10-second period, glassy conditions, and the combined energy is strong (503). That’s a proper session. It’s the best-looking day in the whole outlook – offshore wind, good shape, and a size that’s fun for most.
And then… hold on. Sunday the 13th morning – 10ft of W swell at 12 seconds. The combined energy hits 2502 – that’s extreme. This is no joke. This is big, powerful, and will be way too much for beginners. For experts only. The forecast says it might be too big for this break, and I’m inclined to agree – the river mouth might get unruly, but if you’re charging, it could be a day to remember. This is a serious long-range standout, but with that size comes a lot of risk.
Overall, the best windows are Monday morning the 31st, Saturday morning the 12th, and the glassy dawn patrols on the 5th and 6th. The 13th is for the brave. Expect a few flat days in between, especially mid-week, but there’s enough here to keep the stoke alive.
Stay safe, read the tides, and don’t even think about the 29th.
Rusty.
Short Range ForecastMostly dry. Warm (max 21°C on Mon morning, min 16°C on Fri night). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 30°C on Thu afternoon, min 15°C on Mon night). Wind will be generally light. | ||||||||||||||||||||
Saturday 29 | Sunday 30 | Monday 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | Friday 4 | |||||||||||||||
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) | NW 8 | WNW 8 | WNW 8 | NW 9 | WNW 9 | NW 9 | NW 10 | NW 10 | NW 9 | NW 9 | NW 9 | NW 8 | NW 8 | NW 7 | NNW 6 | NW 6 | NW 7 | NW 6 | WNW 8 | NW 8 | WNW 8 |
Wave Graph | |||||||||||||||||||||
268 | 274 | 280 | 397 | 362 | 338 | 569 | 569 | 414 | 328 | 225 | 98 | 101 | 91 | 155 | 78 | 113 | 144 | 90 | 135 | 54 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | on | glassy | cross-off | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | off | cross-on | glassy | glassy |
High Tide | 4:19AM3.30m | 4:32PM3.52m | 4:52AM3.38m | 5:06PM3.53m | 5:26AM3.40m | 5:42PM3.47m | 6:03AM3.36m | 6:21PM3.33m | 6:45AM3.25m | 7:05PM3.14m | 7:34AM3.08m | 8:00PM2.90m | 8:36AM2.90m | 9:13PM2.68m | |||||||
Low Tide | 10:18AM0.59m | 10:41PM0.50m | 10:52AM0.54m | 11:14PM0.48m | 11:28AM0.56m | 11:50PM0.54m | 12:07PM0.65m | 00:29AM0.66m | 12:52PM0.81m | 1:14AM0.85m | 1:44PM1.01m | 2:09AM1.08m | 2:54PM1.21m | 3:26AM1.28m | |||||||
6:56 | — | — | 6:58 | — | — | 6:58 | — | — | 7:00 | — | — | 7:01 | — | — | 7:01 | — | — | 7:03 | — | — | |
— | 8:14 | — | — | 8:12 | — | — | 8:10 | — | — | 8:08 | — | — | 8:07 | — | — | 8:06 | — | — | 8:04 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 20 | 20 | 20 | 20 | 20 | 17 | 21 | 20 | 16 | 21 | 20 | 18 | 24 | 25 | 22 | 29 | 30 | 27 | 26 | 24 | 21 |
Feels °C | 19 | 20 | 22 | 19 | 19 | 16 | 18 | 17 | 14 | 18 | 16 | 15 | 20 | 20 | 19 | 27 | 27 | 26 | 26 | 24 | 22 |
Swell 1 Height (m) Direction Period (s) | NW 8 | WNW 8 | WNW 8 | NW 9 | WNW 9 | NW 9 | NW 10 | NW 10 | NW 9 | NW 9 | NW 9 | NW 8 | NW 8 | SSW 16 | SSW 16 | NW 8 | NW 9 | SW 14 | WNW 8 | NW 8 | WNW 8 |
268 | 274 | 280 | 397 | 362 | 338 | 569 | 569 | 414 | 328 | 225 | 98 | 101 | 24 | 24 | 18 | 12 | 8 | 90 | 135 | 54 | |
Swell 2 Height (m) Direction Period (s) | — | — | W 10 | — | — | — | — | SW 18 | SW 16 | SW 16 | SW 16 | NNW 8 | NNW 7 | — | NW 10 | NW 9 | SW 14 | N 11 | NNW 6 | SW 13 | NNW 6 |
— | — | 2 | — | — | — | — | 12 | 10 | 10 | 9 | 7 | 5 | — | 4 | 12 | 8 | 2 | 40 | 7 | 27 | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | SW 15 | SW 15 | — | — | SW 15 | — | — | SW 14 | N 10 | NW 10 |
— | — | — | — | — | — | — | — | — | — | — | 9 | 8 | — | — | 8 | — | — | 8 | 2 | 35 | |
Wind waves Height (m) Direction Period (s) | — | — | — | — | — | — | — | NNW 4 | — | — | NW 4 | NNW 6 | — | NW 7 | NNW 6 | NW 6 | NW 7 | NW 6 | — | — | — |
— | — | — | — | — | — | — | 8 | — | — | 16 | 63 | — | 91 | 155 | 78 | 113 | 144 | — | — | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 10 | 116 | 0 | 0 | 100 | 0 | 0 | 100 | 0 | 0 | 100 | 2 | 0 | 151 | 5 | 0 | 191 | 0 | 10 | 0 | 0 |
Best forecast wave conditions in Douro and Minho | |||||||||||||||||||||
Best forecast wave conditions in Portugal | |||||||||||||||||||||
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Information about the Viana do Castelo Surf forecast
The above surf forecast table for Viana do Castelo provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Viana do Castelo can be found by selecting the local surf guide option on the grey menu. Our Viana do Castelo 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 (Viana do Castelo) 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 Viana do Castelo 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.
Viana do Castelo is 3 km (2 miles) from Viana do Castelo. If you plan a holiday in Douro and Minho, look for hotels and other accommodation in Viana do Castelo. Viana do Castelo has rooms for a wide range of budgets as well as car hire and transport links.











