For La Tranche-sur-Mer :
No gale warning.
For the night from Thursday to Friday WNW force 3 becoming NW force 2 in the middle of the night then WNW. Gusts reaching 15 knots in the early part of the night.
Smooth to slight sea. Low from N then fairly long from W in the middle of the night. Excellent visibility becoming good in the middle of the night then good. Daytime of Friday 28 august : The unsettled weather will become more unpredictable in the second half of the day.
Good clear periods alternating with cloudy spells, sometimes dense. Some showers from late morning. In the evening, cloudy spells, sometimes dense.
Possibility of showers WNW wind force 3 continuing all day. Gusts reaching 15 knots in the evening. Smooth to slight sea. Low, fairly long swell from W. Good visibility becoming excellent in the middle of the day.