This exists when a female is seen in her ski/snowboard gear and appears to be really good looking. Later on in the lodge as she removes some layers you realize she's not as good looking as you thought.
See also "Ski Bunny Bummer."
You meet a hot bunny on the chairlift that can really shred and she invites you for a beer just for you to discover she's not so hot after all. This is where you can yell, "Ski Bunny Bummer!!!"