A major winter blast of snow, ice, wind and plunging temperatures in the U.S. stirred dangerous travel conditions from central and southern states all the way to the East Coast early Monday, prompting schools and government offices in several states to close.

Trees dating back almost 6000 years have come to scientists' attention due to ice melting in the Rocky mountains, offering a "time capsule" into the past

Schools as far south as El Paso, Texas, closed due to a polar vortex that has brought historically low temperatures and snowfall to parts of the U.S.

In Indiana, the National Guard was activated to help stranded motorists. The storm was expected to reach the Mid-Atlantic states on Monday and bitter cold temperatures could grip much of the East Coast deep into the South.