Crews were salting roads ahead of the fast-moving clipper storm, and motorists are being urged to slow down on their way to work.
A winter weather advisory is in effect for most of the state, with northern New Jersey, Monmouth County and the Raritan Basin expected to receive the brunt of the snow.
Less snow is expected along the coast, with flurries tapering off or changing to drizzle by the afternoon.
Plows were expected to focus on primary roads, and snow was accumulating on secondary and tertiary roads by daybreak.
The speed limit has been lowered to 45 mph on the New Jersey Turnpike between the Delaware Memorial Bridge and the George Washington Bridge. The speed limit is 50 mph on the Garden State Parkway between Stafford Township and the New York border.
New Jersey Transit trains and buses are cross-honoring tickets all day.