Not stopping in autumn pretty much the trick to winter biking.

After a while you get stubborn enough that new challenges (e.g. ooo, 6 inches of snow fell today and now I have to ride home) actually become fun tests of preparation and stamina and sheer bloody-mindedness.

If you only want to ride when the streets are clear and not through all the snow and slush and shit, then you probably don't need snow tyres at all, especially if you have a mountain bike with those big knobbly tyres.