Heavy snowfall and glacial temperatures shut down much of the central and eastern United States Tuesday -- including the US government -- in a new bout of bad weather in this winter of bone-chilling discontent.

News reports said four people died -- three in Tennessee and one in Kansas -- amid treacherous driving conditions overnight, with blowing snow hampering visibility and roads slippery from ice and slush.

Federal offices were shuttered in Washington, a city legendary for its panicky reaction whenever snow falls.

The decision by the Office of Personnel Management -- the federal agency which makes the official ruling on shutting down the government when the weather turns bad -- was in line with hundreds of local and state offices across a huge swath of the country.

Countless school systems also declared Tuesday to be a snow holiday as a result of this latest arctic blast, which followed a track from eastern Kansas through Tennessee and West Virginia to the mid-Atlantic coast.

As many as 50 million people were in the path of the storm, the brunt of which was borne by the US South, a region which usually enjoys relatively temperate winters.

States of emergency were declared in Alabama, Mississippi, North Carolina, Virginia, and Georgia.

An emergency was also declared in hard-hit Kentucky, where an unaccustomed foot of snow blanketed much of the state, and where the temperature early Tuesday was a frosty nine degrees Fahrenheit (minus one degree Celsius).

The storm, which forecasters dubbed Octavia, also piled fresh snow on mountains of slush and ice that have accumulated over weeks in Boston, New York and other eastern cities.

February has set a record as the snowiest month ever in Boston, with some 10 times the snowfall it would get in a typical winter.

"No end appears in sight as to the brutal winter we have experienced," the NWS wrote in its Boston forecast.

Meanwhile, the National Weather Service warned that more miserable weather is lurking just around the corner.

"The unusually cold weather is forecast to continue through much of the upcoming week for the eastern US," the NWS said in a bulletin early Tuesday.

"Incredibly, another arctic front will arrive to the East Coast by Wednesday night, and this will bring some truly frigid conditions with it."

February has set a record as the snowiest month ever in Boston, with 10 times the snowfall it would get in a typical winter.

Photos of the blanketed city showed snowplows clearing roads and tow trucks rescuing buried vehicles, while officials warned drivers to stay off the roads.

City officials meanwhile temporarily closed the underground train system, making residents not only snowbound, but stir-crazy.

"No end appears in sight as to the brutal winter we have experienced," the NWS wrote in its Boston forecast.

The Flightaware air travel website, meanwhile, said that some 1,800 flights across the United States were cancelled early Tuesday, largely as a result of the bad weather, and another 4,400 were delayed.