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.
Distinguish an island or coastal bulletin from the wider METAREA text and its validity window. Long passages need a reliable method to obtain refreshed warnings offshore; a saved app screen is not one.
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
Ocean swell and the next coastal sector need separate assessment.
The South African Cape coast can change quickly between exposed headlands and shelter inside a bay.
Read SAWS marine warnings and the named coastal or METAREA VII sector; compare swell period, direction and timing at the headland rather than a city observation.
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.
Split the Cape coast by actual headland exposure
A Cape Town departure, an exposed rounding and a continuation toward the south or east coast are separate weather rows. Select the current SAWS coastal or METAREA VII product for the plotted leg and confirm its validity through arrival. The marine portal's forecast and observation categories do not themselves prove a fresh bulletin has been obtained; preserve the issue and source record when you retrieve it.
- South African Weather Service marine portal — METAREA VII marine forecast and observation entry point; live endpoint not obtained in this review Direct product verification is limited; obtain the current issue from the issuer.
- WMO–IMO marine warnings and issuer directory — METAREA service selection; website can have delayed or interrupted products
Wave direction, period and current context
Do not transplant an east-coast current assumption onto every Cape-coast leg. Where the route enters waters affected by a forecast current, retain its spatial and temporal context and compare it with the wave direction. The approach can remain exposed to swell after local wind decreases. A sheltered bay observation is not evidence for the outer headland, and a coarse numerical field cannot determine a harbour entrance's local state.
A staging stop must be independently verified
Compare the full exposed leg with a checked shorter staging plan using revised arrival ETAs and the crew's endurance, not only departure wind. Record the latest reassessment before the headland and the next offshore update opportunity. Current port and navigation instructions remain separate requirements. This guide does not certify an entrance, predict a specific extreme wave or claim a universally favourable Cape departure season.
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.