spearo sea-state engine: consensus of up to 6 models + satellite clarity (ZSD) + buoy-bias checks
Freshness
Re-read every hour, per coast
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.
How we score the water
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.
01
Swell & wave memory
Height, period and direction of the swell, plus the wake of recent storms — an old storm still stirs the water, and the engine remembers.
02
Wind & gusts
Speed and gusts, hour by hour — wind speed and an onshore push chop the surface and cut visibility.
03
Tide phase
Timing and range of the tide, calibrated per coast — big spring tides pull the verdict toward caution.
04
Water temperature
Sea-surface temperature — sharply cold water vetoes a green verdict.
05
Currents & outflow
Direction and drift of the current — it pushes you, and it drags turbid coastal water across where you dive.
06
Rain runoff & air clarity
Rain muddies the water inshore through land runoff, while fog and haze cut visibility at the surface.
07
Coast shape & exposure
How the coast faces the swell — a sheltered cove keeps the water clean; an exposed, head-on point takes a penalty.
Safety gates
Thunderstorm forecast — an instant red, no exceptions.
An official warning (MeteoAlarm / IPMA) — yellow, or red for the higher ranks.
Missing input data — a would-be green is capped to yellow rather than overstated.
Strong disagreement between forecast models — a green day is pulled back to yellow.
Night hours — where night spearfishing is banned by law the window is forced red; where it is legal (Australia outside NSW, New Zealand, South Africa) it is capped at yellow, never green.
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
Entry points with coordinates
Seabed relief — promising ground
This verdict — in your pocket. Open the app for the week's window.
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0 m
Surface
Wind, wave and the swell windows — when to go and the best hours.
spearo.app
no dataupdated 03:32
Gijón — solo, off the rocks
DON'T GO
don't go · wave 2.8 m (occasionally up to ~5.6 m)
wave 2.8 mwind 18, gusts 28 km/hsurge pounding the rocksvisibility ~1 m
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Your best window — with you. Forecast in your pocket.
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−10 m
The water column
Visibility and what drives it — post-storm clearing, river plume, temperature and the thermocline.
What it is
A marine instrument, go / no-go for solo hunting.
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.
Daylight window, sunrise to sunset. The cape wants late summer: from July to September the water is clearer and the sea flatter. Watch the calendar too, because from January to April pollack is catch-and-release under the recreational closure, and here it is a regular target on the drop-offs.
tide
A full Cantabrian range, 4.2 to 4.5 m on springs. On a headland that means current: the ebb pulls westward around the point and you feel it the moment you round it. Get in at slack water and plan your return before the stream picks up, not halfway through the cycle.
shelter
This is the northernmost point of Asturias and it has no shelter at all: the 300°-50° sector comes straight in, and with the NW at 330° it breaks over the drop-offs and over La Erbosa islet. It only works under a high with southerly wind, 160° to 210°, once the long swell has dropped.
conditions
When it really goes flat you get eight to ten metres here, well more than at the head of Gijón bay, because there is no river nearby and no mud. What kills it is the northerly ground swell: two days of long swell and the rebound off the cliff fills the water with particles and bubbles.
hazard
A serious spot, and the key word is galerna: on the Cantabrian coast a hot, still day can turn into a hard NW squall in minutes, and here the swim back is long. The cape sits inside a protected area, so check the current boundaries before you go, and night diving is banned Spain-wide.
access
Park at Verdicio or at Ferrero and walk down to the sand; from there it is a long swim out to the rocks of the cape, so always take a float and preferably a buddy. Never try to exit up the cliff below the lighthouse: with any sea running there is no practicable way out except back onto the beach.
Asturias's northernmost cape; rich grouper-and-sea-bream drop-offs, very exposed, only in calm seas.
Sunrise to sunset, no exceptions. Thermal wind rules here: mornings are calm and from midday on the NE breeze usually sets in and ripples the surface. Since Asturias has no weekday closure, an early Tuesday is the best combination you can get on this stretch.
tide
The tide rules at Estaño more than anywhere else in Gijón: with four and a half metres of range on springs, low water uncovers a field of boulders you have to walk a long way across, and high water eats nearly all the sand. Go down on a half ebb and be back before high tide.
shelter
Cabo Torres blocks the western side: with the NW at 330° the headland cuts part of the wave train and Estaño stays workable when the rest of Gijón is blown out. What it will not forgive is a straight north or a NE from 20° to 50°, which drives right into the cove and fills it with dirty foam.
conditions
A mixed bottom of rounded cobbles and flat rock that clears fast: two calm days give five or six metres. Working against you is the port, because in a NW storm the churned water off El Musel reaches this far turbid, and after heavy rain the runoff from the hillside comes down brown across the beach.
hazard
El Musel is just round the headland and works twenty-four hours a day: port waters are closed under Decreto 25/2006 and you must keep 300 m from working professional boats. Do not cross the point eastward. In summer the sand here is buoyed off as a bathing zone, with its own 500 m.
access
From the Campa Torres road you park at the top and walk down the path and steps to the beach; it is a few minutes of slope and it climbs back harder than it goes down. Enter off the sand and swim left towards the foot of the headland; do not try to get out over the slabs of the point.
Rocky ground to the west below Cabo Torres; partial shelter from NW swell.
Daylight only: across Spain spearfishing ends at sunset. Asturias has no weekday closure, so the best window is first light on a working day, with the clifftop empty and before the afternoon sea breeze swings round and chops the surface.
tide
Cantabrian tides are the biggest in Spain: about 4.2 to 4.5 m on springs and close to 4.9 m on extreme coefficients. At low water limestone platforms dry out and you can walk them; at high water the same ledge is under the wash and stops being a usable exit.
shelter
The shore faces due north and the bad sector runs from 300° to 50°; the NW at 330° is the worst and stands the swell up on the La Providencia slabs. With south and southwest wind, 180° to 225°, it blows offshore and the water flattens under the cliff; a light easterly still lets swell in.
conditions
In calm water visibility sits around five or six metres and improves on the flood; after two days of NW sea the silt lifted off the rocky ground cuts it to little more than one. The Piles river mouth to the west muddies San Lorenzo beach, and that turbidity drifts towards the cape on the ebb.
hazard
San Lorenzo is a buoyed urban beach, and Asturian Decreto 25/2006 closes 500 m around bathing zones plus river mouths, and the Piles empties right here. In summer there is barely any legal water left off the cape, and none of those lines are drawn on any map; measure the distance yourself.
access
You come down from the Providencia clifftop walk: park up by the viewpoint and take the path that cuts across to the stone steps. Wet limestone is very slippery; go in and come out at the same spot, and never use the ledge facing NW when a long northerly swell is running.
Rocky ground east of San Lorenzo beach; sea bream and sea bass, exposed to the NW.
Daylight only, because of the national night ban. Asturias does not close weekdays, and here that matters: this is a promenade coast, and early on a working day there are no swimmers and no rods casting off the rocks. In July and August, forget about the middle of the day.
tide
With a range of over four metres on springs, El Rinconín is not the same place twice: at low water a rock platform appears and you can walk a good way out on it, while at high water the sea reaches the foot of the promenade steps. Pick your entry and exit by the clock, not by what you see on arrival.
shelter
An urban stretch between El Rinconín and Peñarrubia, as open to the north as the rest of the bay: with the NW at 330° the wave rebounds off the promenade wall and the inshore water turns into a washing machine. Southerly winds, 150° to 220°, are the only ones that leave the surface flat.
conditions
Boulders and flat rock in shallow water, so visibility depends on what the sea did over the previous two days: flat calm gives four or five metres, a small northerly chop leaves one milky metre. City rainwater reaches the sea very close by, which does not help either.
hazard
Peñarrubia and El Rinconín are buoyed as bathing zones in summer; Asturian Decreto 25/2006 closes 500 m around them and none of those lines exist on any chart. Add the compulsory 100 m from other people's gear: on this promenade there is always someone fishing from above.
access
Park on the Rinconín promenade by the Madre del Emigrante sculpture and go down the ramps onto the rocks; the algae-covered concrete is slipperier than the stone itself. Enter on a half-rising tide and come out where you went in, because under the wall the wave rebounds and leaves no handhold.
Urban rocky shore to the east; entry from the promenade, moderately exposed.
SOLO 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.
One morning glance — and you know.
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≈
Surfacing
Cameras, map and reference — to hand as you come up.
Live cameras, map & reference
Cameras · live
Look at the water right now.
Check the cam BEFORE you leave. Foam, brown/green murk, or waves washing the entry rocks = No-go. At night/in fog the cam is useless — treat it as «unknown», NOT «green».
✓Spearfishing licence mandatory; the AUTONOMOUS COMMUNITY issues it (not the State) and it is valid in the exterior waters of the whole coast. Free-diving only — scuba is banned (, art. 3).
✓Spearfishing catch may not be sold or traded — it is non-commercial fishing ().
✓Night prohibited: spearfishing only in daylight (sunset to sunrise not allowed) — , art. 16.d.
✓Marker buoy MANDATORY: mark your position with a clearly visible buoy and stay within 25 m of it — , art. 15.
✓Never keep the speargun loaded out of the water — , art. 16.a.
✓Keep at least 300 m from professional fishing vessels that are working — , art. 12.b.
✓The state act (, art. 16) bans, for spearfishing: a loaded gun out of the water; explosive/electric points and lamps (hand torches excepted); underwater scooters; night — from sunset to sunrise. Plus art. 12 b), d), e): 300 m from professional fishing vessels, light as an attractant, poisons/explosives. A ban in a PARTICULAR reserve, port or beach comes from that place's OWN instrument (the reserve's order, the autonomous community's rules, the port authority) — see the no-take zones on the map and your community's rules.
✓Min. sizes by ( + + EU 2019/1241): sea bass 42 cm (rec.) / 36 cm / 25 cm Mediterranean / 22 cm Canaries; gilthead bream 20 cm and white seabream 23 cm in the Mediterranean (EU 2019/1241); grouper 45 cm. See your zone's species card.
✓Only species in Annex I of may be taken; keeping, landing or transporting undersized specimens is prohibited.
✓The licence needs a medical fitness certificate for free-diving and civil-liability insurance (or a federative licence, which includes it). Mandatory in the Basque Country/Murcia/Asturias/Galicia; the federative licence covers it in Galicia/Balearics/Cantabria; the Canaries and Andalusia do NOT require it for the individual licence (a responsible health declaration). Minimum age generally 16 (14 in Andalusia).
Safety protocol
Sets: watch the wave trains ≥15 min before entering; Hmax ≈ 2×Hs, the wash can run 50 m past the foam line. A lull >10 min with period >12 s = a big set «overdue», do NOT enter; enter right after a full set passes and re-check at minute 30.
Exit FIRST: find your exit AND a backup before entering. On a rocky/boulder shore a 0.5 m rise in swell can make the exit impossible — getting pinned/unable to climb out is the main killer.
Headland rip: prominent points often have a permanent topographic rip regardless of the model — locate it, enter/exit on the windward side, never swim against it.
Cold: wetsuit per the SST chip; the first shiver = a metabolic surge and a drop in breath-hold → get out at the first steady shiver. Cap the session at 45–60 min below 15 °C.
Solo discipline: buoy up; tell someone the spot and exit time; conservative breath-hold (never push it in cold/murky/surfy water); visibility <3 m — don't enter.
Afternoon wind: on many coasts the wind builds from midday — plan to be out of the water by midday; the chop builds — get out.
UV 11:00–15:00 (UVI ≥6): sunscreen and cover up on the surface interval.
Solo is a fundamental risk (hypoxic blackout with no buddy). Any doubt = No-go.
FAQ — spearfishing in Gijón
Where can I spearfish in Gijón?
Gijón has rock entry points such as Cabo de San Lorenzo / La Providencia, El Rinconín / Peñarrubia and Cabo Peñas (Verdicio). Gijón faces due north onto the Cantabrian Sea, so NW and N seas set the agenda. Below you'll find each spot (access, shelter and hazards) and today's forecast.
When is the best season in Gijón?
Summer and early autumn are the windows — in winter the Bay of Biscay swell shuts the coast down. Tides are large (4 m+) and set up current, so pick a small-sea day with the tide in your favour.
How cold is the water in Gijón?
~14–22 °C: cool, but it warms up in the summer window. A 5 mm suit at peak summer, 7 mm with a hood the rest of the year.
Is Gijón good for a beginner?
Demanding: strong Biscay swell, big tides and exposed rock entries. It's for those who can already read the sea and pick the window well — not a coast to start on.
Do I need a licence in Gijón?
Yes — in Gijón you need a recreational sea-fishing licence (issued by the autonomous community); breath-hold only (no scuba), with a marker buoy and no night diving. See the guide.
✓There is no fixed national catch cap (, art. 5 delegates it to the communities); the standard is 5 kg/person/day, with 1 specimen allowed not to count (Canaries — Decreto 182/2004, art. 38.3; Murcia; Galicia; Basque Country). Protected species have per-piece quotas.
✓Only a harpoon is allowed — hand-held or mechanically propelled, with one or several points (, art. 14.1). Carrying spearfishing gear and underwater breathing equipment aboard AT THE SAME TIME is prohibited (art. 14.2) — an offence in itself, even if you dived on a breath hold.
✓Spain is not one jurisdiction. The licence is issued by a coastal autonomous community, and you must comply with the rules of the administration on whose littoral you are in the water: «debiendo cumplir la normativa establecida por la administración en cuyo litoral se realice la actividad» (, art. 13). Interior waters — inside the straight baselines: bays, coves, rías, the whole coastal strip — are the community's competence; exterior waters are the State's. So the age, the days of the week, the distances and the are found in your community's act, not in the state one.
✓Asturias: the spearfishing licence is issued by the Principado de Asturias — spearfishing is part of the maritime licence (www62.asturias.es).
✓Asturias: the spearfishing licence authorises 5 kg of fish taken exclusively on a breath hold, with no underwater breathing apparatus of any kind (Decreto 25/2006, art. 5.2); it takes an official medical fitness certificate and accident + civil-liability insurance (art. 6.2), and it lasts two years (art. 7). The cap is 5 kg per licence per day, the excess of the biggest fish not counted (art. 8.1). Orto to ocaso only (art. 9). Barred within 100 m of fixed or floating gear, of anglers' rods and of fishing vessels, within 500 m of bathing zones, in port areas, in river mouths (rías excepted) and over marine-culture areas (art. 12.2). Buoy red, orange or yellow; the gun is unloaded entering and leaving the water (art. 12.3).
⛔ Seahorses (Hippocampus) — protected (RPE).
Rules change and are REGIONAL. Before heading out, check with the competent autonomous community (licence) and the min-size table in force.
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