A northwesterly, weak and very variable flow prevails over the West and the North of the basin. Over the South-East, it is southerly, weak and particularly variable.
For Berck sternes :
No gale warning.
For the night from Thursday to Friday NNW force 2 in the early part of the night turning NNE. Gusts reaching 15 knots in the early part of the night.
Slight sea becoming smooth to slight at the end of the night. Low, short swell from W. Excellent visibility. Daytime of Friday 21 august : The sky will remain changeable.
Good clear periods alternating with cloudy spells, sometimes dense. Risk of showers in the morning, possibility of a few spots in the afternoon. In the evening, cloud and long sunny periods.
No precipitation. NNE force 2 turning NNW force 3 in the middle of the day then N. Gusts reaching 13 knots in the evening. Smooth to slight sea. Low, short swell from W. Excellent visibility.