The warning published by the Maritime Authority for Wednesday and Thursday (17th/18th December) forecasts waves that can reach 7 meters high on the high seas, which will give rise to a strong swells near the west coast of mainland Portugal. The IPMA has placed seven coastal areas of the mainland plus two areas in Madeira for high seas which may reach a maximum of 9-11 meters.

The National Maritime Authority and the Navy recommend precautions particular by the fishing community and those undertaking  recreational boating, to return to the nearest port of call and to adopt precautionary measures, as well as seek other information of port authorities on the conditions of access to ports, and avoiding going out to sea until conditions improve.

For the general population that frequent the coastal zones anywhere along the entire western coastline, it is advised that until the end of Friday people refrain from walking along the coast and on the beaches, as well as undertaking activities in areas exposed subject to to maritime unrest. People should avoid exposing themselves to unnecessarily risks.

If there is an absolute need to travel to the coast, a vigilant attitude must be maintained and always be aware that in these extreme conditions the sea can easily reach apparently safe areas.

It is emphasised that recreational anglers take extreme caution, avoiding fishing along the cliffs and upstream areas on the coastal fronts hit by wave surf, always bearing in mind that the sea in these extreme situations often reaches areas which are thought to be secure.