I live in Florida, and I can say 100% for sure that it will get too hot in the summer and too cold in the winter. If you want to keep your snakes in the garage you will need to get a small window unit air conditioner to keep the temperatures in check. I know from first hand experience that my garage gets far too hot in the summer and too cold in the winter so please do not tell me otherwise.

I think that it would be much easier to put other things in the garage, and keep your snakes inside.