For La Tranche-sur-Mer :
Warning fresh gale.
We are 85% sure of the situation, because in this type of situation, it is difficult to define precisely when the precipitation will begin.
Skies changeable to very cloudy. No precipitation in the morning, heavy showers towards the end of the day. In the evening, very cloudy skies to overcast.
Light showers. SW force 4 freshening S force 6 in the middle of the day then WSW force 8. Gusts reaching 52 knots in the evening. Slight sea becoming moderate in the middle of the day then rough. Low, short swell from SW. Excellent visibility.