No winter biome in Minecraft server?

Alright, so I’ve gotten around a large area of the server, and with all the buildings and whatnot it’s over 60 megabytes, but this is waht is confusing me. I can’t find a winter biome! I really want a winter area, specifically a mountain range, but I haven’t seen a spec of snow or ice. Is there some reason it wouldn’t have been generated?

If it doesn’t appear in server maps, or aside, is there a map editor that allows me to create mountain ranges? I could winterize them a bit with the /snow command, but a tool to make a mountain range would be usefull.

Also, if I use the command to make it snow in one area, will it naturally snow like in a biome after a while?