thundersnow
n.— «The storm did come with a novelty act as residents were treated to a rare meteorological phenomenon called thundersnow, which is caused from the upward motion of a cold front when temperatures are near freezing. And that thunder folks heard on Friday morning was nearby, for the snowfall acts as an acoustic suppressor of the thunder. » —“Snow surprise” by Bob Fenske Forest City Summit (Iowa) Nov. 14, 2006. (source: Double-Tongued Dictionary)