Snowstradamus 

an individual who comments on the fact that inclement weather is expected, in such a way as to imply that he or she is the first or only person who pays attention to weather forecasts

75 of your friends on facebook write "SNOW'S COMING!" your response to all of them: "thanks, snowstradamus, for telling me what 74 other people and the morning news already told me."

Snowstradamus by kira ai January 14, 2011

Snowstradamus 

The type of person who continually talks about the amount of snow your area is expected to get, often complaining or acting fearful several days before it will happen. Will refer to anything more than 2 inches as a "Snowpocalyspe" or "Snowmaggedon".

Victor: "Did you hear Amy carry on about how its supposed to snow all weekend?"
Lisa: "Yeah, she is a real Snowstradamus. Its really getting old."

Snowstradamus by manderjean March 13, 2014