Normandy weather will be a bit unpredictable in late October, probably a mix of rainy days and bright blustery days unless you are lucky. If you start from Paris and are comfortable driving, I’d suggest a loop taking in Normandy (stop at Monet’s garden in Giverny on the way), Brittany (Mont St Michel/St Malo and the area around Vannes/Carnac/Quiberon are both nice) and coming back via the Loire Valley and Chartres.