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Reef, rock and kelp 5–18 m, boat; bass, pollack, sea bream. Slack water only.
Google MapsToday — sit it out. 🌫 Murky all week after the storm — the water isn't settling
Sources & confidence
Compiled by the spearo sea-state engine · How it works →
The verdict comes from seven water factors and hard safety gates — not ten tabs. Go or stay.
Our own model
Our own forecast engine — not a third-party widget. It weighs these water factors into one go-or-stay verdict for this coast; the 0–10 dial is that verdict, read out as a number.
Safety gates
It all folds into a single 0–10 score and one verdict: go or stay.
A forecast, not a guarantee — the sea has the last word.
Where to get in, where to hunt
Leave your email — and the moment a window opens at Île de Sein, we'll send the go / no-go verdict. Email is all we need.
Every covered town has its own live forecast, cameras and entry points. Choose where you're diving.
What's missing? Tell us what you'd like to see — new spots, species, data or features. We read everything.
Wind, wave and the swell windows — when to go and the best hours.
The day is picked above, in the hero. Here are that day's windows, the hour-by-hour map and the trends. Tap a window to break down the conditions.
Visibility and what drives it — post-storm clearing, river plume, temperature and the thermocline.
spearo.app folds wind, wave, swell period, visibility, tides, water temperature and risk into a single verdict — go to the spot or not. It computes 7 days ahead from open marine models (Open-Meteo, IPMA), with no sign-up and no accounts. Built for solo spearfishing off the rocks, where any mistake costs dearly.
Now live: 1391 spots across 205 stretches of coast — mainland Portugal, Madeira and the Azores.
See all spotsRelief and bottom type, tides, and the depths of each spot.
The models set the window. Whether you go in is read only at the water: count the sets, watch the surge on the entry. If in doubt, you don't get in.
Scouted entries, coloured by today. The colour is the sea state at the spot, not a guarantee: the wash and a slippery entry you judge on site.
Open the seafloor mapReef, rock and kelp 5–18 m, boat; bass, pollack, sea bream. Slack water only.
Google MapsThe full spot briefing is part of the subscription: entry, bottom, hazards, tide window.
Open in the appCameras, map and reference — to hand as you come up.
transparency ~9 m · satellite, yesterdaysatellite estimate · may differ right at the shore
The full spot briefing is part of the subscription: entry, bottom, hazards, tide window.
Open in the appRocky point to the west, rock and kelp 3–16 m, shore; bass, pollack, sea bream. Slack water only. Strong current.
Google MapsThe full spot briefing is part of the subscription: entry, bottom, hazards, tide window.
Open in the appEdge of the reef plateau to the west, 5–20 m, boat (advanced); pollack, bass, structure. Extreme current — experts, strict slack. Coords approx.
Google MapsThe full spot briefing is part of the subscription: entry, bottom, hazards, tide window.
Open in the appCove to the north, rock and kelp 1–14 m, shore; bass, pollack, sea bream.
Google Maps⛔ Spearfishing is BANNED here — the Île de Sein port approaches, closed to spearfishing. The spot stays on the map to mark the closure: find a legal stretch on the no-take map.
Google MapsSOLO is the biggest risk: underwater you can black out from lack of oxygen silently and fatally, with no one around. Solo is never truly «safe». Below are the best weather windows; carry a buoy, tell someone your plan and exit time, and any doubt — don't go.
Rules change. Exact distances from beaches/ports and seasonal closures are set by the local préfecture maritime — check its arrêté and the DIRM/OFB zone map before heading out.
Île de Sein has rock entry points such as Roches sous le vent (port), Bord de la Chaussée de Sein and Beg al Lann. A low, wild island west of the Raz de Sein, expert territory, full stop. Below you'll find each spot (access, shelter and hazards) and today's forecast.
Summer (June–September) — the most reliable. West Brittany faces the open Atlantic: meso-tidal, big swell and wind shut the exposed side fast — stay on the lee capes and islands (Ouessant, Molène) in the calms.
Open Atlantic: ~11 °C in winter, ~16–17 °C in summer (capes cooler from upwelling). 7 mm hooded. Clear water in the calms, but swell stirs up murk fast at the entries.
Hard: open Atlantic, big swell, upwelling chills the water. For experienced divers who read the swell forecast; the windows are short and demand discipline.
No paid licence in Île de Sein — but third-party (RC) insurance is MANDATORY, and since 10/01/2026 a free EU registration + catch declaration (RECFishing app) applies from age 16. Breath-hold only (no scuba), buoy mandatory, no night; sizes by coast (bar 42 Atl. / 30 Med.), grouper and corb banned in the Med. See the guide.