A snowy scene at Colgate University in Hamilton, N.Y., on Wednesday morning. (stevedickinson via Instagram )

Heavy snow is falling in upstate New York on Wednesday as the week’s coastal winter storm lingers over the Northeast. As much as 18 inches of snow had fallen through the late morning hours in locations around Syracuse and Albany, N.Y. since Tuesday night. Interstates 81 and 481 remain dangerous for travelers around Syracuse on Wednesday afternoon, where the Weather Service warns of snowfall rates up to 2 inches per hour.

After causing heavy rain along the I-95 corridor on Monday and Tuesday, the coastal storm began to push cold, Canadian air south into the Northeast U.S. on Wednesday night, prompting what had been falling as rain and a wintry mix to change over to snow.

The snow has been falling wet and heavy, especially around Albany, where temperatures have been hovering just above the freezing mark for most of the morning. The Albany area wavered between periods of snow and since Tuesday night, when thundersnow was reported around 6 p.m.

Around Syracuse, snow has been persistent and at times heavy since around 11 p.m. on Tuesday night.

Northeast radar snows snow continuing to fall across parts of upstate New York south into northern New Jersey, as well as Vermont and western Massachusetts. (Weather Underground)

A portion of Interstate 81 south of Syracuse has been closed due to heavy snow on Wednesday morning. Syracuse.com has been tracking the traffic mess:

Update: (11:42 a.m.) The southbound I-81 closure has been extended to the I-481 ramp in Syracuse. The highway is closed to southbound traffic between Exit 17 and Exit 14. 

Update: (11:07 a.m.) Traffic is finally moving on I-81 as drivers are making their way to the LaFayette exit, said Steve Trowbridge, who was stuck on the road for more than 2.5 hours and almost ran out of gas. “It looks pretty clear above us,” Trowbridge said

Around 11 a.m., the National Weather Service in Binghamton, N.Y., issued a special weather statement warning of heavy snow causing dangerous travel conditions around Syracuse:

Before switching to rain in the morning, Albany County saw as much as 4 inches of snow since Wednesday night. Schoharie and Schenectady counties (to the north and west of Albany) have both seen as much as 15 inches of snow, and Greene County (to the south) accumulated a maximum of 14 inches.

To the northwest, Onondaga County, N.Y., which is the location of the I-81 shutdown, has seen as much as 20 inches of snow through 1:20 p.m. on Wednesday. Madison County has also accumulated 18 inches, and Cortland County has seen up to 15 inches.