I have a very dim memory of maybe one of the B3350's having an airfilter clog up with snow, and then not be able to regenerate properly. The guy never wrote back, so we didn't find out what all happened.
I know this is likely not what you mean as the covers I made are to keep branches away from the plastic kubota grill when I'm using the grapple. I don't think they would be of much use for snow but here in Florida we don't get much of that
Read about problems with snow from a snowblower being sucked into the air intake on B2650 and B3350 tractors. May have been on a different forum. Solution on the B2650 was to pull the end of the air snorkel from above the radiator, and bend it so that it pulled air from behind the radiator. For summer operation the snorkel should be reinstalled in the factory location so it pulls in cooler air.