This is a pre-passage source and decision desk, not a current forecast or clearance to depart. The map is centred approximately on the area, not on your route or a forecast-zone boundary.
National forecast responsibility changes quickly across these coasts and straits. Check the exact marine zone, tropical-system alerts where applicable, visibility and the latest local port or traffic notices.
1. Primary sources
Open current bulletins and warnings for every sea area on the route. These links are starting points, not a promise that each covers the whole location; if unsure, identify the issuer through WMO–IMO.
2. Route and local effects
Remote island passages need current local authority information and a data backup.
Raja Ampat voyages move through island lee, open channels and remote anchorages with limited connectivity.
Use BMKG maritime warnings and named waters; check rain squalls, channel current and a reliable offline update plan rather than relying on a downloaded model image.
How to use this source set
Start with the warning, then the marine text for the exact named area. If the route crosses a zone boundary, obtain both bulletins. Note issue and valid times, wind units and the meaning of wave height. Where a link opens an agency portal, navigate to its current marine product; a homepage is not itself a forecast.
Compare with an exposed station or buoy if available. Check its position and observation time: a sheltered station does not overturn a warning for an open channel. If a bulletin is missing or stale, identify the issuing service via WMO–IMO and defer the decision until current information is available.
Before-passage check
- Mark departure, exposed legs, arrival and feasible diversions; find the responsible named marine areas for each.
- Check warnings, issue and valid times; assess conditions when you expect to reach each leg, not only at departure.
- Compare wind and gusts, waves and swell, visibility, thunderstorms and local effects; do not infer a strait from a sheltered harbour.
- Compare recent observations where available, noting their time and exposure; a mismatch calls for another check.
- Set the next bulletin check, a reassessment trigger, an alternative and a backup communication channel.
Model map — optional
Windy is a third-party model display, not the issuer of official warnings. Choose a layer and check its valid hour and model run. Nothing loads until you click.
Without JavaScript, open the map separately.
If connectivity fails
Before departure, save the current official text bulletin and warning with issue time. Arrange another way to receive updates, such as an appropriate coastal broadcast, NAVTEX or satellite channel. A saved map cannot replace new warnings.
How to choose weather tools · All sailing areas
Scope: Source list assembled 25 September 2026; check its freshness and coverage before use. This public area guide is not a current personalised forecast, navigational notice service or safety verdict. Personalised forecasts with AI and experts are in closed testing; public booking is not open. The skipper makes the decision.
Raja Ampat is not one BMKG point
BMKG's catalogue lists northern Raja Ampat, Raja Ampat–Sorong and Misool waters as distinct named choices. A Sorong–island circuit and a remote Misool continuation therefore need different source selections. Verify the actual route against the product coverage and retain the original name alongside translation. Do not infer that a nearby city forecast or a whole-archipelago map resolves the same exposed channels.
- BMKG named Indonesian waters — Bali/Lombok subdivisions and Raja Ampat/Misool sectors; select actual route
Remote channels need an evidence-gap log
Separate wind and wave predictions from locally applicable current, reef and anchorage information. A calm-looking island lee cannot establish the next channel's current or swell exposure. Note where a representative observation is absent and where the forecast grid is too broad for a narrow approach. Avoid borrowing an unverified current speed or generic reef-entry rule from another island group.
Make offline planning about updates, not screenshots
Before leaving connectivity, save the latest official text with issue and validity and establish how the next warning can be received. Compare the remote itinerary with a shorter checked circuit using exposure, daylight and crew endurance. If the next product cannot be obtained, show that limitation explicitly. A stored map is past evidence; it does not become a continuously valid forecast when the boat enters a remote anchorage.
- BMKG named Indonesian waters
- WMO–IMO marine warnings and issuer directory — METAREA service selection; website can have delayed or interrupted products
Editorial review of this material: 27 September 2026. This date concerns the page content; check current forecast issue times and validity at the original sources.