- window
- From sunset to sunrise spearfishing is prohibited (DPR 1639/1968, art. 129): the window is entirely a daytime one. Spearfishing on breath-hold is allowed by day; at night it is banned under DPR 1639/1968. The last stretch, the 740 m out to ten metres of water, is the one you will swim tired: put it in the day's arithmetic. A shore oriented at 188° loses the sun before sunset: take it into account for the last descent.
- tide
- The right question on this coast is not what the tide is doing but what swell has been through. With a range that small the entry rock sits at the same level at any hour. At Chia the level changes little, but the current towards the south can be noticeable in the channels. If the current takes you past the 740 m of the ten-metre line, head straight back for land.
- shelter
- You are in the lee in Tramontana; the moment the wind goes south, the water under the shore dirties. In a bay like this the shelter is a few tens of metres wide, tucked against the windward point rather than in the middle of the arc, and in a hard Ostro not even that. With the wind from the north at your back you can work; with the swell from the south in your face you look and go home. A metre of long swell from the south is worth more than two metres of short chop raised inshore.
Chia spearfishing forecast — wind, swell, visibility & live cameras
Today — right on the edge — wave, wind and visibility.
Sources: IPMA · buoys · Copernicus · Sentinel-2 — high confidence · data 13:01
Sources & confidence
- Sources
- IPMA · NDBC & IH buoys · Copernicus Marine · Sentinel-2
- Method
- spearo sea-state engine: 6-model consensus + 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.
- 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.
- Wind & gusts
- Speed and gusts, hour by hour — wind speed and an onshore push chop the surface and cut visibility.
- Tide phase
- Timing and range of the tide, calibrated per coast — big spring tides pull the verdict toward caution.
- Water temperature
- Sea-surface temperature — sharply cold water vetoes a green verdict.
- Currents & outflow
- Direction and drift of the current — it pushes you, and it drags turbid coastal water across where you dive.
- Rain runoff & air clarity
- Rain muddies the water inshore through land runoff, while fog and haze cut visibility at the surface.
- 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
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