Locally (Ontario, Canada) 0 to 15 F are typical night time temperatures and 15 to 20 for the daytime highs at this time of year.
Winter is fine, I'm used to those kinda temperatures and enjoy the freshness of winter much more than the suffocating humidity of summer. Summer heat kills all ambition and drives me indoors to hide in the air conditioned basement.
That being said, I don't think that extreme cold is good for airguns, especially PCPs, as everything gets sluggish and performance/consistency suffers.
A .22 rimfire is best winter rabbit hunting and it's time for 10 meter indoor shooting.
Cheers!