New York, January 2 (RHC)-- The torrent of arctic air that poured into many parts of the United States this past week tightened its grip over the New Year and brought record cold to some spots, as weather forecasters and experts warned of dangerous conditions. 

As far south as Charleston, South Carolina, freezing rain coated the city's landmark church steeples, while a shroud of ice blanketed rock faces next to Niagara Falls as mist from the thundering falls on New York's border with Canada froze in the bitterly cold air. 

North Dakota and northern Minnesota were among the coldest spots in the United States over the past several days, prompting the National Weather Service (NWS) to issue a winter chill advisory for the region. 

Temperatures in northern North Dakota plunged to around -30 F (-34.4 C) over the weekend with a wind chill of about -50 F (-45.5 C), said Ken Simosko, a meteorologist with the weather service in North Dakota. 

Maine Governor Paul LePage declared a state of emergency to allow heating oil truck drivers to work beyond the limit of hours set by federal transportation rules.  While most U.S. homes are heated with natural gas, much of the northeast relies on heating oil that is delivered to homes by truck. 

Canada has also issued extreme weather alerts and was forced to scale back some of its New Year's Eve celebrations.  The cold weather pattern is expected to persist for several more days, before warming up again toward the end of the week.