I always cover my Grady in central NC, despite the lack of snow on an annual basis.   We got hit with 6 inches on Thursday in the Raleigh Durham area.   The cover handled it fine.   I just went out the next day and knocked the snow off.  Anyway, I like to keep the rain, pollen, dirt, etc.  out of the boat.  Keeps it looking good year round.     Go for the cover!