A snowblower assembly for removing snow from a paved surface, such as roadways and airport runways. The snowblower assembly includes a snowblower assembly that defines an open interior that encloses a pair of rotating side augers and a rotating impeller. The snowblower housing includes a lower leading edge that is recessed behind the blade tips of the rotating impeller. The sidewalls of the snowblower housing each include a recessed lower sidewall edge to reduce the buildup of snow within the snowblower housing. A side plate extension is mounted to each of the sidewalls to modify the volume of the open interior defined by the snowblower housing to accommodate different types of snow.