Backdoor
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Hourly Forecast
Timezone: Europe/Lisbon
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Saturday 6
Sunday 7
Monday 1
Tuesday 2
Wednesday 3
Thursday 4
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Backdoor surf guide

Backdoor is a popular surf spot that usually comes alive during the summer months. It works best with N-NW swells and can attract quite a crowd when the waves are right. This spot is known for its challenging conditions, making it more suitable for experienced surfers who are looking for a test of their skills.

The surf here can handle swells starting from around 3ft (approximately 0.9 meters) and can reach up to double overhead. The waves break over an uneven reef, forming nice, hollow sections that can get pretty intense. Most of the waves break to the right, and the best time to surf is during mid tide with east winds, which can provide some cleaner conditions.

With its expert level demands, Backdoor isn't for beginners. When it's firing, it can be crowded, so be prepared to share the waves with other skilled surfers. It's important to respect the locals and the vibe of the spot, as it can get hectic, especially when the waves are good.

Surf reports and surf forecasts nearby Backdoor

Coxos
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Crazy Left
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Ribeira d'Ilhas
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Reef
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Reef
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Backdoor
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Pedra Branca
Lisboa, Portugal
Reef break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Praia do Norte
Lisboa, Portugal
Beach break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Praia do Peixe
Lisboa, Portugal
Beach break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Furnas
Lisboa, Portugal
Beach break
Sat 16
Sun 17
Mon 18
Tue 19
Wed 20
Thu 21
Fri 22
Sat 23
Sun 24
Mon 25
Tue 26
Wed 27
Wind certainty

Wind certainty tells you how much the weather models agree on the forecast.

  • High certainty: Models agree closely; forecast is reliable.
  • Medium certainty: Some disagreement; conditions may shift slightly.
  • Low certainty: Models diverge; treat forecast with caution.

We calculate this by comparing wind speed, gust and direction from multiple models (like GFS, ECMWF, Arome, and Harmonie) and seeing how closely they match. They are weighted, meaning that some models count more than others, depending on how good they are for a certain spot.

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Forecast Cheat Sheet

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Models and Updates

Surfnerd blends multiple global and local wind and swell models using advanced interpolation and spatial techniques to create an "ensemble" forecast. Forecasts are refreshed hourly.

Surf Predictions

Our AI-driven algorithm scores surf quality, shown by green, orange, and gray dots. Each forecast hour is rated for wind, swell, and tide quality, then combined into an overall score. Here’s the scale:

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