Offering a favor you don't expect to be accepted, but is.

when one gets owned/snapped/smashed.
after either falling or getting a good call /comeback against them.

Ask any hospital worker... this is when a person who is hooked up to system monitoring devices, dies. When they die, the monitor turns to snow - there's no information on it anymore.

An appropriate gesture to rude or idiot skiers that turn out in front of people without giving a care in the world.

Getting Snowed is when someone comes to a fast decline in speed while turning their skis or snowboard angled at the idiot, causing a wave of powdery snow to engulf the mentally inept skier