THE PILOT LANDED ON THE HIGHWAY THE NIGHT BEFORE DUE TO BAD WEATHER CONDITIONS ENCOUNTERED EN ROUTE. HE ATTEMPTED TO TAKEOFF ON THE SNOW COVERED HIGHWAY THE NEXT MORNING. THE PILOT COULD NOT MAINTAIN DIRECTIONAL CONTROL DURING THE GROUND RUN AND THE AIRCRAFT COLLIDED WITH A SNOW BANK ON THE LEFT SIDE OF THE ROAD, THEN NOSED OVER.