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
Island shelter and the Malacca approach need distinct weather and navigation checks.
Langkawi and Malaysia’s west coast lead into the Malacca Strait, with distinct island and strait exposure.
Read MetMalaysia’s marine shipping area and current warnings; compare squall timing, visibility and traffic constraints at the intended crossing.
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.
Select the shipping region deliberately
METMalaysia's shipping page defaults to a named region such as Northern Straits of Melaka; a loaded page is not proof that your entire west-coast itinerary has been selected. For a Langkawi departure, confirm the route's region and change the selector for each onward section. Note the wind units before comparing with a knots-based app and keep marine warnings separate from the daily weather table.
- METMalaysia shipping forecast — Select named shipping region; default Northern Straits of Melaka not every Malaysian coast
Squalls and background flow
Regional Singapore research identifies Sumatra squalls as a relevant Strait of Malacca weather pattern, but that is not a prediction of a squall on today's route. Use the current warnings and available radar or observations to assess the immediate weather picture. A quiet marina wind does not rule out an approaching rain band. Retain visibility and the actual exposed-leg timing, especially before a traffic-heavy coastal crossing.
- Singapore CCRS / MSS Sumatra-squall research — Regional squall context, not a current squall forecast Direct product verification is limited; obtain the current issue from the issuer.
- METMalaysia shipping forecast
Separate coastal progress from current and entry checks
For an onward island or coastal leg, compare the departure alternatives at the next approach ETA and the following return or continuation. Obtain applicable tidal/current and harbour information independently; daily marine weather does not establish local stream phase or entrance depth. If crossing into Thailand, add the TMD shipping source for the corresponding waters rather than treating a national border as a model-data boundary.
- METMalaysia shipping forecast
- Thai Meteorological Department shipping forecast — Gulf and Andaman/Malacca sections; current warning must be read directly Direct product verification is limited; obtain the current issue from the issuer.
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.