Paris & Normandy in October

I'd expect good temperate weather, generally, though of course bad weather is possible at any time. October is off-peak, so fewer crowds for sure. However, for some places you may also see shorter hours, so it is hard to make a blanket statement about lines. But overall things should be less crowded. Note there's going to be less daylight than in peak months, less even than in Vancouver Island. That might affect your plans in Normandy but probably not in Paris. I think of October as a very good time to travel to France. Have fun!

We were in Paris and Normandy in October 3 years ago. When we got to Paris around the 7th, the weather was gorgeous - sunny and in 70sF. We then left after three days and headed toward the Loire, then to Normandy. By the time we got to Normandy around the 15th, the weather had turned much cooler (mid-50s) and rainier. If you can, I'd go to Bayeux earlier, when it'll probably be warmer - those beaches get pretty cold in a cold wind!

Paris weather is more predicable, but Normandy, on the coast can have four seasons in one day. We were in wool sweaters under lined raincoats at the end of July two years ago. The high was in the fifties. But a couple days later it was probably in the 70s. It's a nice time to travel these places.

One small disappointment about Paris in October is that the ornamental gardens in the parks are cleaned out on what appears to be a civil-service schedule rather than any obediance to Mother Nature. So, even if the weather is balmy and the flowers are still blossoming happily, they are pulled out.
Go anyhow. You're used to changeable weather.

My husband and I did the same trip two years in a row in October. There were virtually no lines at any of the sites--except Versailles on a Sunday--we were warned. The weather was mild (on the cool side) during the day, a bit chillier in the evening. Some rain, but not enough to ruin the trip.
Have fun!