It is seldom that simple.
I have ridden in a foot of snow and as low as 5F.
It is more of an interest thing for me.
If I want to ride I will regardless of the temp. If there is a pile of snow on the ground I may take my mountain bike out to have fun.
Other times I have no desire and would rather sit on a trainer.
You should see the stupid crap I get myself into when I have cabin fever.