Usually they won’t pull you over for something like a quarter inch, but you should still clean it off because they could get you in trouble if they wanted to. I had one friend leave some snow on (she’s really short and didn’t have any tools to wipe it off since she had to throw her old one away) and she didn’t get pulled over but she doesn’t make a habit of it. Another person I know legit got pulled over for like a half inch (he’s just a lazy asshole). Really depends.