do you have entrance reducers on? do you have an upper entrance/exit for the bees to fly out? like iddee, i would just leave it, unless i see it to start icing over, i tip my hives a little forward so the water from respiration runs out, if it's iced it won't. once inawhile i will go through and brush some of it away, the hard crusty stuff, but not usually fresh snow unless its real icy/sleety/snowy stuff.