Plan the open Cook Strait leg, chosen Sounds entrance and protected interior separately, with written forecasts and locally qualified current information.
Use the written coastal product for the open leg
Identify the named coastal product for the actual track, including Cook and any adjacent coverage required by the chosen route. MetService's Nelson marine desk links written coastal forecasts alongside point boating output; these are not interchangeable. Read warning, wind, sea, swell and visibility text for the planned stage, preserving issue and validity. A Wellington departure forecast alone does not describe the full inter-island crossing and arrival inside the Sounds.
An entrance decision is not the sheltered interior forecast
Separate the open strait, the selected entrance and the next sheltered-water stage in the ETA plan. Queen Charlotte Sound / Tōtaranui and Tory Channel / Kura Te Au need their own navigation context and current authority advice. An apparently calm mooring deeper inside does not validate the approach. Verify the actual destination, access and waiting arrangements without borrowing commercial ship procedures as automatic instructions for a private yacht.
The Tory Channel arrows are a hybrid model
The council's current display combines observation inputs with hydrodynamic modelling to represent local flow. Check the time slider, input or feed status and the point being inspected; a future view is a prediction, not a future measurement. The model must not be described as a current meter at every arrow. Compare its qualified local guidance with the expected wind and sea, keeping uncertainty visible rather than labelling a model-selected moment safe.
Picton tide height is not Tory Channel slack
Keep LINZ tide-height information separate from the channel-specific current product. Confirm the actual location, date and local-time convention before comparing departure and entrance ETA. Do not invent a constant offset from Picton high water to a flow reversal elsewhere. If the chosen model or reference lacks usable current information at the revised time, retain the missing-data condition and obtain suitable local advice before relying on the entrance plan.
Check notice dates and observation availability
Use the council's current harbour notices and feed-status information before relying on a local wave or weather observation. An indexed report about a buoy being unavailable may later be cancelled; a visible historical trace does not prove that the sensor works today either. Save the observation timestamp and distinguish the measured variable from the model output. A missing wave observation is not evidence of no waves; failing to retrieve a warning is not evidence that no warning is in force.
Stress-test the arrival before the committed crossing
For a Wellington-to-Sounds plan, compare the open-water stage and entrance at both planned and slower ETAs. A delay can change flow, light, warning validity and the usability of a waiting place at once. Resolve those checks before the next committed stage rather than assuming the sheltered destination removes the approach problem. Keep a documented alternative and update channel; this page provides a preparation method, not a plotted route or clearance to transit.
Official products by task
- MetService Nelson / Cook coastal product desk — Find the written Cook and other relevant coastal forecasts and warnings for the leg. Point boating ratings are a separate model product and do not establish a Tory Channel stream window.
- MetService marine responsibilities and coverage — Understand inshore, coastal and ocean service responsibilities. A responsibility description is not today's bulletin, its warning or an exact route intersection.
- Marlborough District Council Harbours — Local harbour limits, navigation material, weather feeds and directions for Marlborough Sounds. Confirm the current document and its applicability to the vessel type.
- Marlborough Tory Channel current and tide model — Local model blending observation inputs with hydrodynamic information. Check selected time, input/feed status and model coverage; displayed arrows are not measurements at every point.
- Marlborough current harbour notices — Check dated notices affecting access, aids, observations and local operations. Verify expiry or cancellation; an old indexed notice is not proof of a current restriction or outage.
- LINZ tide predictions and reference locations — Official New Zealand tide tables, including daylight-saving treatment and secondary-port information. High-water time is not slack water in every nearby channel.
Countries and local sources
- New Zealand
Read written marine forecasts and local hydrographic context together; keep automatic point ratings, tide heights and current models distinct.
Map orientation
The approximate area centre is not an approach waypoint, a track, a depth survey or a forecast-zone boundary. The third-party map loads only after your click.
Prepare a passage brief
Bring route timings, vessel and crew profile together with checked sources and reassessment triggers. Personal AI analysis and expert review are in invitation-only closed testing. An editorial geographic page does not extend the calculation service’s actual coverage.