Surf Forecasts:
Viana do Castelo surf forecast from 23 Aug 2026:
- Best quality surf: Thursday 27 Aug, 10PM (local time) - 16ft (5.0m), 12s period, W swell with cross-onshore winds.
- Most powerful swell: Friday 28 Aug, 1AM (local time) - 16ft (5.0m), 13s period, WNW swell with 8,102 kJ wave energy.
- Next surfable swell (1★+): Monday 24 Aug, 1AM (local time) - 6ft (1.9m), 9s period with SW 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 Monday (Aug 24) at 1AM. The primary swell is predicted to be 1.9m and 9s period with a secondary swell of 0.3m and 8s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Viana do Castelo in the next 16 days are 5.0m 13s and forecast to arrive on Friday (Aug 28) at 1AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.4m 4s period and expected on Monday (Aug 24) at 7AM.
| Wave Type | Time (WEST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 1AM (Mon 24th Aug) | 6ft (1.9m) 9s |
| Best Surf | 10PM (Thu 27th Aug) | 16ft (5.0m) 12s |
| Most Powerful | 1AM (Fri 28th Aug) | 16ft (5.0m) 13s |
Table - best surf conditions forecast for Viana do Castelo over the next 16 days.
The Lowdown
G’day, Rusty here. Let’s break down what’s happening at Viana do Castelo for the next couple of weeks.
We start off a bit slow, no real standout surf until the end of the week. The river mouth here is fairly consistent, but it needs the right conditions. The water is 62° – that’s about 4° colder than usual for this time of year, so you’ll want a thick wetsuit.
Sunday the 23rd afternoon is a little bright spot early. Light rain, a light cross-off breeze from the ESE at 6 mph, and a clean 4ft swell from the west with a 10-second period. The combined energy is moderate at 373. Nothing huge, but clean and fun.
Then we hit a long stretch of nothing. From Monday the 24th through Thursday the 27th, it’s mostly poor. Rain, onshore winds, and messy swell. The swell gets up to 7ft by Thursday afternoon, but it’s a short 8-second period and onshore at 19 mph – not worth it.
Friday the 28th morning is a tricky one. Swell is 8ft from the WNW with a long 11-second period, and the combined energy is strong at 1555. The wind is light and onshore from the WSW at 3 mph. But it’s too big for this break. Experts only, and even then, the river mouth might not like it. The afternoon is similar at 7ft but still too big.
The first real standout is Saturday the 29th morning. Clear skies, glassy conditions with a light SE breeze at 3 mph, and a clean 5ft swell from the NW with a 9-second period. Combined energy is moderate at 293. This is the best early session – clean, fun, and the river mouth handles it well. Crowds are often, so expect company.
Sunday the 30th is smaller and cleaner but only 3ft, with the wind picking up later.
The next standout is Monday the 31st morning. Clean again, with a cross-off breeze from the NNW at 9 mph, and a 5ft swell from the WNW with a 9-second period. Combined energy is moderate at 323. Solid, clean session. The afternoon is also clean but windier.
Tuesday the 1st of September morning is another good one – light cross-off breeze, 5ft from the NW, 9-second period, clean.
We get a drop in size through the 2nd and 3rd, but still clean. The 4th and 5th are marginal, but Saturday the 5th morning has a nice offshore breeze from the NNE at 3 mph and a clean 4ft swell from the NW. Good for a sneaky session.
The best of the whole forecast is Sunday the 6th of September afternoon. Clear skies, light cross-off breeze from the NW at 6 mph, and a 4ft swell from the NW with a very long 11-second period. Combined energy is moderate at 628. Clean, lined-up groundswell with good shape. Crowds are often, but for that quality, it’s worth it.
Monday the 7th gets messy again with cross-shore wind and onshore in the afternoon, though the afternoon has a massive 20-second period groundswell from the west at 5ft – combined energy of 2246. A lot of energy, but with onshore wind, it’s a gamble. Experts might check the tide.
Pick your days: Saturday the 29th morning and Sunday the 6th afternoon are the best. The whole run from the 31st to the 1st of September is also solid. Get out there.
Rusty.
Short Range ForecastHeavy rain (total 49mm), heaviest during Tue night. Warm (max 21°C on Tue afternoon, min 17°C on Tue night). Mainly fresh winds. | Days 5-7 Weather SummaryHeavy rain (total 33mm), heaviest during Wed night. Warm (max 20°C on Wed afternoon, min 15°C on Fri night). Winds decreasing (fresh winds from the SW on Thu afternoon, calm by Thu night). | |||||||||||||||||||
Sun 23 | Monday 24 | Tuesday 25 | Wednesday 26 | Thursday 27 | Friday 28 | Saturday 29 | ||||||||||||||
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) | W 10 | SW 9 | SSW 8 | SSW 8 | SW 7 | W 8 | W 7 | WNW 6 | SSW 5 | WSW 7 | W 8 | WSW 8 | WSW 8 | WNW 13 | WNW 11 | WNW 10 | WNW 9 | NW 9 | NW 8 | NNW 8 |
Wave Graph | ||||||||||||||||||||
306 | 560 | 601 | 545 | 203 | 90 | 69 | 50 | 91 | 217 | 542 | 373 | 615 | 8102 | 1555 | 874 | 351 | 293 | 196 | 88 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross | cross-on | on | cross-on | on | cross | on | on | cross-on | on | on | cross-on | on | cross-on | glassy | glassy | cross | glassy |
High Tide | 1:23AM2.50m | 1:39PM2.77m | 2:09AM2.67m | 2:21PM2.96m | 2:45AM2.85m | 2:56PM3.15m | 3:17AM3.02m | 3:28PM3.31m | 3:48AM3.18m | 4:00PM3.44m | 4:19AM3.30m | 4:32PM3.52m | ||||||||
Low Tide | 7:10PM1.41m | 7:18AM1.41m | 7:57PM1.22m | 8:02AM1.23m | 8:34PM1.03m | 8:39AM1.04m | 9:07PM0.85m | 9:12AM0.85m | 9:38PM0.69m | 9:45AM0.70m | 10:09PM0.57m | 10:18AM0.59m | 10:41PM0.50m | |||||||
— | — | 6:52 | — | — | 6:52 | — | — | 6:54 | — | — | 6:54 | — | — | 6:56 | — | — | 6:56 | — | — | |
8:23 | — | — | 8:22 | — | — | 8:21 | — | — | 8:19 | — | — | 8:16 | — | — | 8:15 | — | — | 8:14 | — | |
mm | 6 | 5 | 9 | 4 | 6 | 1 | — | 9 | 9 | 3 | 16 | 5 | 3 | 5 | 1 | — | — | — | — | — |
Temp °C | 20 | 20 | 19 | 20 | 19 | 20 | 21 | 18 | 19 | 20 | 17 | 19 | 18 | 18 | 20 | 20 | 18 | 20 | 20 | 18 |
Feels °C | 20 | 20 | 16 | 18 | 20 | 20 | 20 | 18 | 18 | 17 | 15 | 14 | 13 | 16 | 19 | 19 | 18 | 19 | 19 | 19 |
Swell 1 Height (m) Direction Period (s) | W 10 | SW 9 | SSW 8 | N 7 | SW 7 | W 8 | W 7 | WNW 6 | W 6 | WSW 7 | W 8 | NW 9 | NW 8 | WNW 13 | WNW 11 | WNW 10 | WNW 9 | NW 9 | NW 8 | NNW 8 |
306 | 560 | 601 | 4 | 203 | 90 | 69 | 50 | 39 | 217 | 542 | 190 | 132 | 8102 | 1555 | 874 | 351 | 293 | 196 | 88 | |
Swell 2 Height (m) Direction Period (s) | SW 6 | NNW 8 | NNW 7 | SW 13 | N 6 | SSW 6 | SSW 6 | NW 10 | NW 9 | NW 8 | — | S 11 | — | — | — | — | NNW 10 | — | — | W 7 |
56 | 11 | 5 | 7 | 1 | 37 | 25 | 15 | 21 | 18 | — | 2 | — | — | — | — | 251 | — | — | 44 | |
Swell 3 Height (m) Direction Period (s) | NNW 8 | SSW 13 | SW 13 | — | SW 13 | N 6 | NW 11 | SW 12 | NW 6 | NW 6 | — | — | — | — | — | — | — | — | — | — |
11 | 16 | 7 | — | 6 | 1 | 5 | 6 | 8 | 1 | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | — | — | — | SSW 8 | — | — | — | SSW 6 | SSW 5 | — | — | WSW 8 | WSW 8 | — | — | — | — | — | — | — |
— | — | — | 545 | — | — | — | 12 | 91 | — | — | 373 | 615 | — | — | — | — | — | — | — | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 0 | 0 | 100 | 114 | 106 | 104 | 170 | 18 | 331 | 104 | 247 | 277 | 247 | 114 | 87 | 104 | 0 | 0 | 104 | 0 |
Best forecast wave conditions in Douro and Minho | ||||||||||||||||||||
Best forecast wave conditions in Portugal | ||||||||||||||||||||
Header Global | ||||||||||||||||||||
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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.











