I’m no wizard myself, but I imagine that it must get awfully cold in the halls of Hogwarts school. If you are with team gryffindor, you might want to keep warm with this Harry Potter Gryffindor House Beanie Hat.
It looks stylish and proudly displays your affiliation for all the other students to see. It’s an officially licensed beanie made of lambs’ wool and features the Gryffindor Coat of Arms patch.
You could always use magic to get warm, but maybe you broke your wand. In which case, just buy this hat. One size fits most. $8.99 from Entertainment Earth.