The Sarasota area of SW Florida has a very pleasant climate with year-round cycling and very diverse groups of avid cyclists. This morning, my wife and I (in our mid 60s) rode our tandem 32 miles in 70degF (21C) with a group of 60- and 70-year-olds who cruise at 18+ mph. Tomorrow I shall ride with 35-50 year-olds.
There are few hills, a lot of bike lanes and a great cycling community. Our neighbours are from Toronto.
I should add that we are originally from the UK, so any weather is better than that. We live here year-round.