
Surf Forecasts:
Viana do Castelo surf forecast from 5 Aug 2026:
- Best quality surf: Thursday 6 Aug, 1AM (local time) - 4.5ft (1.4m), 6s period, NW swell with cross-offshore winds.
- Most powerful swell: Wednesday 5 Aug, 10PM (local time) - 4.5ft (1.4m), 8s period, NW swell with 281 kJ wave energy.
- Next surfable swell (1★+): Wednesday 5 Aug, 4AM (local time) - 2ft (0.6m), 11s period with NNW 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 Wednesday (Aug 05) at 4AM. The primary swell is predicted to be 0.8m and 8s period with a secondary swell of 0.6m and 11s. 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 1.4m 8s and forecast to arrive on Wednesday (Aug 05) at 10PM. 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 6s period and expected on Thursday (Aug 06) at 7PM.
| Wave Type | Time (WEST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 4AM (Wed 5th Aug) | 2ft (0.6m) 11s |
| Best Surf | 1AM (Thu 6th Aug) | 4.5ft (1.4m) 6s |
| Most Powerful | 10PM (Wed 5th Aug) | 4.5ft (1.4m) 8s |
Table - best surf conditions forecast for Viana do Castelo over the next 16 days.
The Lowdown
Alright, Rusty here, looking at the extended forecast for our little corner of the coast. Let's be honest, it’s a slow start and a long wait for anything worth getting excited about. The first week and a half is mostly blown out or just too small to bother, with a real gap of nothing good from now until well into the second week.
We’re looking at Viana do Castelo, a river mouth setup that needs everything to line up just right. Water temp is sitting about 64.9°, which is pretty normal for this time of year, nothing unusual there.
For the first several days, it’s a mess. Tuesday the 4th is a write-off with weak 3ft swell from the west and a cross-onshore breeze. Wednesday the 5th morning cleans up a bit with a 2.3ft NW groundswell (10-second period) and a cross-offshore wind, so the lines might be clean but there’s hardly any push. The combined energy is weak (181). It’s surfable, but only just. Thursday the 6th morning is similar, clean but tiny at 3ft and a short period of 6 seconds. The rest of that week and into the weekend is mostly cross-shore chop and tiny waves. Saturday the 8th morning goes glassy with a tiny 1ft swell—it’s a lake, not surf.
There’s a slight tease on Monday the 10th morning with glassy conditions and a 1.6ft NW swell, but the energy is minimal (51). You could paddle around, but you won’t be catching much.
The real drama shows up a long way out, over a week from now. On Tuesday the 18th of August, the models are hinting at a serious spike. We’ve got a massive 7.2ft to 7.5ft NW swell rolling in, with the combined energy going ballistic at 933 to 1211. The period hits 10 to 11 seconds, so it’s got proper grunt. The wind is glassy on that Tuesday morning and light cross-shore in the afternoon. But here’s the thing—this break just can’t handle that much water. The forecast is telling us the swell is too big for the river mouth. It will be dangerous and unsurfable for most, maybe just for absolute experts on the biggest sets, and even then it’s iffy. It would be more of a show than a session.
The only real standout that could actually be ridden is on Wednesday the 19th of August. The swell drops back to a still-chunky 5.2ft from the NW, with a clean cross-offshore wind (NNW, 6 mph). The combined energy is still strong at 427, and the period is 9 seconds. This is the best bet on offer—a solid, clean, powerful wave that might be a bit much for beginners at that height, but for any intermediate or better surfer, it could be a proper session at the river mouth. Just be aware that crowds are likely here on a good day, so get there early.
Overall, it’s a grim first 12 days, then a window of big, tricky surf. The 19th is your best shot for something actually rideable.
Short Range ForecastMostly dry. Warm (max 24°C on Thu afternoon, min 16°C on Wed night). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 22°C on Sat morning, min 16°C on Fri night). Wind will be generally light. | ||||||||||||||||||||
Wednesday 5 | Thursday 6 | Friday 7 | Saturday 8 | Sunday 9 | Monday 10 | Tuesday 11 | |||||||||||||||
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 10 | NW 9 | NW 6 | NNW 8 | W 10 | NNW 7 | NW 8 | NW 8 | W 9 | W 9 | W 8 | NW 11 | NW 10 | NW 9 | NW 8 | NW 7 | NW 8 | NNW 11 | NW 10 | NW 10 | NW 9 |
Wave Graph | |||||||||||||||||||||
96 | 193 | 149 | 59 | 53 | 120 | 62 | 46 | 25 | 24 | 29 | 35 | 48 | 81 | 44 | 60 | 86 | 204 | 139 | 134 | 81 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-off | cross | glassy | on | cross | cross-off | glassy | cross | cross-off | cross-off | cross | cross-off | glassy | cross | cross | cross-on | cross-on | glassy |
High Tide | 8:01AM3.03m | 8:22PM2.99m | 9:00AM2.92m | 9:28PM2.82m | 10:14AM2.85m | 10:51PM2.72m | 11:39AM2.88m | 00:21AM2.76m | 12:59PM3.03m | 1:36AM2.92m | 2:03PM3.24m | 2:36AM3.11m | 2:56PM3.43m | 3:26AM3.28m | |||||||
Low Tide | 2:06PM1.03m | 2:36AM1.00m | 3:12PM1.17m | 3:46AM1.14m | 4:37PM1.24m | 5:10AM1.19m | 6:07PM1.17m | 6:33AM1.11m | 7:22PM0.98m | 7:41AM0.95m | 8:22PM0.76m | 8:37AM0.77m | 9:12PM0.57m | ||||||||
6:31 | — | — | 6:33 | — | — | 6:35 | — | — | 6:35 | — | — | 6:37 | — | — | 6:37 | — | — | 6:39 | — | — | |
— | 8:49 | — | — | 8:47 | — | — | 8:45 | — | — | 8:45 | — | — | 8:44 | — | — | 8:42 | — | — | 8:40 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 22 | 21 | 19 | 23 | 24 | 21 | 23 | 22 | 18 | 22 | 22 | 19 | 22 | 22 | 18 | 22 | 22 | 19 | 22 | 22 | 18 |
Feels °C | 19 | 18 | 18 | 21 | 21 | 21 | 23 | 21 | 17 | 21 | 21 | 18 | 20 | 20 | 17 | 22 | 21 | 20 | 22 | 23 | 19 |
Swell 1 Height (m) Direction Period (s) | WNW 8 | W 8 | NNW 8 | NNW 8 | NNW 8 | NNW 7 | NW 8 | W 9 | W 9 | W 9 | W 8 | W 7 | W 7 | W 7 | NW 8 | NW 7 | NW 8 | NNW 11 | NW 10 | NW 10 | NW 9 |
65 | 28 | 64 | 59 | 53 | 120 | 62 | 26 | 25 | 24 | 29 | 35 | 35 | 23 | 44 | 60 | 86 | 204 | 139 | 134 | 81 | |
Swell 2 Height (m) Direction Period (s) | NW 10 | WNW 10 | WNW 10 | W 10 | W 10 | NNW 8 | W 9 | SW 13 | NNW 7 | NW 4 | NNW 6 | NW 11 | NW 10 | S 13 | W 7 | W 7 | NW 12 | W 6 | WNW 10 | WNW 9 | W 11 |
96 | 34 | 34 | 49 | 48 | 21 | 27 | 7 | 10 | 2 | 4 | 30 | 48 | 3 | 24 | 15 | 72 | 7 | 19 | 17 | 59 | |
Swell 3 Height (m) Direction Period (s) | WNW 10 | SW 12 | SW 12 | SW 12 | SW 12 | WNW 10 | S 11 | — | SW 12 | NNW 7 | NW 12 | N 6 | — | — | W 12 | NW 9 | W 7 | WNW 10 | W 6 | W 6 | W 5 |
20 | 6 | 6 | 6 | 5 | 30 | 2 | — | 6 | 4 | 6 | 1 | — | — | 3 | 23 | 15 | 10 | 6 | 2 | 1 | |
Wind waves Height (m) Direction Period (s) | — | NW 9 | NW 6 | NW 5 | NW 6 | — | — | NW 8 | NW 4 | — | — | — | — | NW 9 | NNW 6 | — | — | — | — | — | NW 4 |
— | 193 | 149 | 30 | 52 | — | — | 46 | 8 | — | — | — | — | 81 | 63 | — | — | — | — | — | 6 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 130 | 0 | 0 | 182 | 0 | 18 | 180 | 0 | 267 | 111 | 0 | 0 | 151 | 0 | 0 | 100 | 10 | 104 | 100 | 0 |
Best forecast wave conditions in Douro and Minho | |||||||||||||||||||||
Best forecast wave conditions in Portugal | |||||||||||||||||||||
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
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.











