Meteorologists and maritime authorities call for caution. There is a risk of submersion.
An “atypical” situation during this summer period, according to meteorologists. From Tuesday, August 26, the French Atlantic facade is faced with an unusual meteorological phenomenon: a cyclonic swell. Directly linked to Hurricane Erin which hit the East Coast of the United States last week, this swell, combined with significant tidal coefficients, generates large-scale waves. They could reach “4 to 5 meters” high. The risk is all the higher since swell is accompanied by a baïnes phenomenon, particularly risky sea currents for sea users and vacationers.
Faced with this swell, Météo-France has placed six departments in vigilance vague-submersion: Côtes-d’Armor, Finistère, Charente-Maritime, Gironde, Landes and the Pyrénées-Atlantiques. Local authorities have implemented preventive measures to protect people and infrastructure. In Biarritz, the red flag was hoisted. In several municipalities such as Lacanau and Biscarrosse, swimming and nautical activities are prohibited at least until Thursday morning. In Royan, the town hall called on the inhabitants and tourists to avoid the coast two hours before and after the full seas.
Concretely, a cyclonic swell is a series of waves formed by the violent winds of a cyclone in the open sea. When a cyclone turns at sea, its strong winds blow relentlessly on a large area of ocean. This action of the wind transfers energy to the surface of the water and forms large waves. These waves propagate long distances and can reach several meters in height, several days after the dissipation of the cyclone. This kind of meteorological event fortunately remains infrequent in France.
The message of the authorities and meteorologists is clear: despite the good weather, the risk at sea is very real, and caution is in order to avoid a dramatic assessment at the end of the summer season. It is important to keep informed of marine forecasts by consulting the Côtes Bulletin.
