Today — right on the edge — wave, wind and visibility.
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 Yakushima, we'll send the go / no-go verdict. Email is all we need.
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: 3016 spots across 406 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 mapRock-ringed tide pools on the south-east coast, good for snorkelling without tanks; depth not published. Hand spear only — no speargun, no scuba.
Google MapsCameras, map and reference — to hand as you come up.
Japan: spearguns and scuba/hookah are banned for all recreational fishers nationwide (Fisheries Agency prefectural gear table); a hand spear (yasu) is allowed only in some prefectures (e.g. Okinawa, Kagoshima, Nagasaki, Kochi, Mie); abalone, lobster, octopus and sea urchin in fishery-right areas belong to the local co-op, and marine park zones are closed. Check current rules locally.
South-coast beach entry with an easy entry for a shore dive; a coral channel runs out from the entry and rocky crevices drop to about 35 m. Hand spear only — no speargun, no scuba.
Tank-shita at Isso is entered over rocks from shore (also dived by boat); 3–18 m inshore, 30 m further out. Exit is hard at spring low tide. Hand spear only — no speargun, no scuba.
Google MapsSouth-coast beach dive with the whitest sand on the island among rocks, channels and tunnels; max 18–25 m. Long walk to the entry; toilets and a simple shower. Marine park zone — take nothing.
Google MapsReef, boulder reef, 3–20 m, from shore. Hand spear only — no speargun, no scuba. Coords approx.
Google MapsDived from inside Onoaida harbour, under 10 m in the basin (to ~20 m outside); used when the north coast is rough. Watch boat traffic. Hand spear only — no speargun, no scuba.
Google MapsNorth-coast beach dive at Shitoko, shallow coral and rubble, max 18–20 m; only in flat calm as entry is difficult with waves. Hand spear only — no speargun, no scuba.
Google MapsNorth-west beach dive at Yoshida with good shallow coral and a porites head offshore with resident green turtles; max about 25 m. Hand spear only — no speargun, no scuba.
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.
Yakushima has rock entry points such as Isso, Nagata and Kurio. The mountain island at the meeting of the Kuroshio and temperate water — boulder reefs, rays and turtles off Isso and Nagata in the north-west and the coral marine-park zone at Kurio in the south-west. Below you'll find each spot (access, shelter and hazards) and today's forecast.
April–November; July–October is typhoon season, and the winter northerly monsoon roughs up the sea.
21–22 °C in February, 29–30 °C in August — 3–5 mm in winter, 1.5 mm in summer.
Coral reefs and drop-offs, currents in the channels. Spearguns and scuba are banned nationwide — only a hand spear (yasu), where the prefecture allows it; shellfish, lobster, octopus and urchin in fishery-right areas belong to the co-op.
Yakushima: Japan: spearguns and scuba/hookah are banned for all recreational fishers nationwide (Fisheries Agency prefectural gear table); a hand spear (yasu) is allowed only in some prefectures (e.g. Okinawa, Kagoshima, Nagasaki, Kochi, Mie); abalone, lobster, octopus and sea urchin in fishery-right areas belong to the local co-op, and marine park zones are closed. Check current rules locally.
