Snow falling on East Main Street is one of the better things Riverhead does — the marquee glowing, the river running black beyond the storefronts, flakes turning slow through the streetlights. It is also a night's work, because by morning every walk and every parking space has to be open. Bohemian Rose Designs LLC clears snow through those hours, plowing drives and lots, shoveling entryways and steps, and putting down salt and sand exactly where feet will land. Storms here arrive wet and heavy off the water and then freeze hard behind the front, so getting out while it is still falling is most of the craft. There is something quietly satisfying about a doorway that looks like winter never happened.