- Temperature
- Feels like
- Rain
- Wind
- Sea water
- Waves
- Updated
Sea water: 16.4°C, cooling slightly to around 15°C over the coming days
Waves: 1.3m
At 16.4 °C the water in Castelo do Neiva is cold. Without a wetsuit, a swim stays short.
Sunrise: 07:45 · Sunset: 18:57 · Day length: 11h 13m
| Day | Sea water | Waves |
|---|---|---|
| Monday 12/10 | 16.4 °C | 1.3 m |
| Tuesday 13/10 | 16.2 °C | 1.2 m |
| Wednesday 14/10 | 16.4 °C | 1.3 m |
| Thursday 15/10 | 16.2 °C | 1.3 m |
| Friday 16/10 | 16.0 °C | 1.4 m |
| Saturday 17/10 | 15.7 °C | 1.3 m |
| Sunday 18/10 | 15.2 °C | 1.1 m |
| Month | Average water |
|---|---|
| January | 13.8 °C |
| February | 13.7 °C |
| March | 14.2 °C |
| April | 15.6 °C |
| May | 15.8 °C |
| June | 17.3 °C |
| July | 16.5 °C |
| August | 16.2 °C |
| September | 16.5 °C |
| October | 17.9 °C |
| November | 16.6 °C |
| December | 14.8 °C |
Monthly averages for 2022–2025.
This page shows the water temperature at Castelo do Neiva today and over the next seven days, so you can pick the best beach day before you go.
Sea temperature moves much more slowly than air temperature. A hot afternoon does not warm the ocean, and a windy day can cool it fast. Checking the water itself is the only reliable way to know what to expect.
Castelo do Neiva is a quiet parish south of Viana do Castelo, with a small fishing beach and the wider Amorosa sands just along the coast. It faces west into the Atlantic on one of the most persistently upwelled stretches of the Portuguese shore, so the water hovers around 16.3 °C even at the peak of summer. Rock outcrops break the sand into pockets here, which gives a little shelter from the swell but none from the cold.
The water is warmest in October, averaging 17.9 °C, and coldest in February at 13.7 °C. This is Portugal's coldest water: upwelling is at its most persistent here and holds the warming back even at the height of summer.
The ocean gains and loses heat far more slowly than land, so it runs months behind the seasons. On top of that, the summer northerly wind pushes surface water offshore and draws cold deep water up in its place, which is why a heatwave on land so often coincides with a colder sea.
This is a quiet stretch of coast for walking, beachcombing and a fast swim, with far fewer people than the beaches either side of it. The wider Amorosa sands nearby pick up enough swell for surfing, and the rock pools between the sand pockets are worth exploring at low tide. Small-scale fishing still goes on from the beach.