Is the farm open when its raining?

Yes

Yup

I don't know. My guess is as long as it's not pouring rain then it will be. But there are a lot of hills within the property and I would imagine that going in the rain would pose quite a few challenges.

I believe they're open but prepare to get messy and maybe bring a change of shoes. Busy little ones may need a change of pants / outfits. Have fun.

I think so. I believe they close for the season on or around november 1. Great place to visit.