When I lived in New York we had winter, but it was never too bad, and in January we would always have a two- or three-week period, a sort of second "Indian Summer" where the temps would range from the mid-60s to the mid-70s. At those times I could work outside, and I would always get my favorite catcher and do lots of throwing, work on a new pitch or my control or whatever. When it got too cold, I always found a gym or some other venue where I could work without freezing my tush off. So I always found ways to stay in shape. And when there was sufficient snow---a few inches usually---I made snowballs and threw curves and what-not with them, and have you ever seen a snowball break sharply the way a slider or a palm ball would do?
So I say to our correspondent in Quebec, go thou and do likewise. 8)