Someone who is into winter sports and tends to go to the mountains often. Experienced skier/snowboarder.
"Do you want to go to the pass next week?"
"Yeah man, I go every week."
"Dude, you're such a snow rat."
1. Someone who plays in the snow or sleds during the ski season instead of doing a real winter sport ie. snowboarding or skiing.
2. Someone who drives all the way up to the pass so they can play in the snow, usually annoying to real snow-sport participants, usually takes up alot of the good parking so snow-sporters have to walk extra far with heavy equipment.
"Dude. There's no place to park up here."
"Yeah all the snow rats took up all the fuckin parking spots!"