State police spokesman David Procopio said troopers responded to numerous crashes and spinouts caused by icy roads, some involving their own cruisers. Drivers were urged to reduce speeds and leave extra time.
Worcester canceled school for the day and other communities delayed the start of classes.
The National Weather Service posted a flood watch for urban and poor drainage areas, and a coastal flood advisory for the midday high tide cycle from 11 a.m. to 3 p.m.
In Vermont, the National Weather Service in Burlington is predicting snow to fall from midday Tuesday through most of Wednesday, with 6 to 12 inches expected in northern and central Vermont. Black ice on roads was the problem Tuesday morning on Interstate 89 between Exits 10 and 8. Police have temporarily closed one southbound lane in Middlesex after a truck went off the road.
Forecasters say the southern two counties of Windham and Bennington could get somewhat less snow, with rain and sleet mixing in.
In areas where the precipitation remains all snow, it's expected to be of the wet, heavy type.
In Connecticut, icy rain has made roads slick and dangerous, causing more than a dozen accidents and shutting parts of Interstates 91, 84 and 691 in Connecticut.
Several accidents involving tractor-trailers were reported early Tuesday morning.
No major injuries have been reported.
Conditions may worsen as a winter storm approaches. A wintry mix is expected to develop this morning and then change to rain in the afternoon.
Precipitation totals could reach 1 to 2 inches.