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São Martinho do Porto
São Martinho do Porto / Foz do Arelho (Lagoa de Óbidos)
9.4→ Steady
Flat calm
Now
🌊 16.0°CwaterSeaModerate2kn WUV0 LowTide2.3m ↓falling · low in 4 h 46 min
calmest 08:00 · 8.9
Hour by hour
| Time | Calm | Swell | Wind | Tide | water |
|---|---|---|---|---|---|
| 08:00 | 8.9 | 0.2m | 12kn NNE | 1.6m ↑ | 16.0°C |
| 09:00 | 8.7 | 0.2m | 12kn NNE | 1.9m ↑ | 16.0°C |
| 10:00 | 8.7 | 0.2m | 12kn NNE | 2.2m ↑ | 16.0°C |
| 11:00 | 8.6 | 0.3m | 11kn N | 2.5m ↑ | 16.0°C |
| 12:00 | 8.4 | 0.3m | 11kn N | 2.6m ↑ | 16.0°C |
| 13:00 | 8.1 | 0.3m | 12kn N | 2.5m ↓ | 16.0°C |
| 14:00 | 7.8 | 0.3m | 14kn N | 2.3m ↓ | 16.0°C |
| 15:00 | 7.6 | 0.4m | 14kn N | 2.0m ↓ | 16.0°C |
| 16:00 | 7.6 | 0.4m | 14kn N | 1.6m ↓ | 16.0°C |
| 17:00 | 7.6 | 0.4m | 13kn N | 1.3m ↓ | 16.0°C |
| 18:00 | 7.6 | 0.4m | 13kn N | 1.1m ↓ | 16.0°C |
| 19:00 | 7.6 | 0.4m | 12kn N | 1.1m ↑ | 16.0°C |
| 20:00 | 7.6 | 0.4m | 12kn N | 1.2m ↑ | 15.9°C |
Know before you get in very weak/inconsistent surf most days · boat traffic near the harbor and inlet · crowded swim/surf shared space in summer
Swim alerts
How this is calculated
Flatness is modelled from the wave forecast. Rips, flags and lifeguards are not in this data — always judge the beach in front of you.
Guides Beach Day Checklist: Portugal Coast Conditions · Snorkeling Conditions in Portugal: How to Read Them · Tides and Surf Portugal: Best Tide for Surfing