Malevil (1981)

In southern France, in a quaint little town, the mayor, who also owns a castle with some cattle, is in the wine cellar with some other people--the pharmacist, the veterinary, and some of his employees. As they are drinking wine, they hear a terrible noise and the heat's getting higher and higher. They don't realize what's happening: when they come out of the cellar, they realize that everything has burned, and all the buildings are destroyed.