How we compute

Before suggesting a route, the Seadromy engine does what a careful skipper does when planning a passage: it reads the weather, checks the seabed, looks for shelter and always keeps a way out. Here is what it checks.

Weather analysed, not copied

Several forecast models are compared hour by hour for wind, gusts and swell. When they disagree, the reading turns cautious: for safety the strongest model counts, and the app tells you when the models no longer agree. Gales are spotted in advance and the voyage is built around them: tucked in before they arrive, under way again once they ease.

Routing tailored to your boat

Every crossing is routed with your boat's polar, whether monohull, catamaran or ketch: point of sail, tacks to put in, motoring when the wind dies or comes on the nose, fuel consumption and range. The route clears headlands, islets and shoals with a safety margin, and departure times are weighted to arrive in daylight.

An anchorage chosen for the night ahead

The shelter of each place is rated for all eight wind directions, from the sea that can get in and the residual swell that sets a boat rolling at anchor. The engine looks at the night's wind, not the afternoon's, rules out anchorages where the swell gets in and always keeps a sheltered bolt-hole nearby.

Seabed and depth

Depth is estimated around the anchoring spot from bathymetry, with clearance under the keel based on your draught. The type of seabed, sand, seagrass or rock, is noted for holding and to protect the seagrass meadows. These are estimates: the echo sounder and the chart have the final say.

Places checked one by one

Anchorages, coves and ports are listed, then checked one by one: access, swimming zones, mandatory moorings, protected areas, villages, restaurants and provisioning ashore. For each area, ports of refuge and bolt-holes are identified, as are the large towns, which are avoided for the night.

The rhythm of a real voyage

The engine balances each day's distance, comfort on board and the urge to explore: it avoids pointless back-and-forths, alternates nights at anchor and in port, and never exceeds the limits you set for gusts, nights at sea or hours under way.

Seadromy prepares your passage; it does not replace it. The chart, local rules and a look at the day's conditions remain essential, and the skipper decides.