The cascade at Niagara Falls was a scene of steam, snow and ice amid the polar vortex. (Rick Warne / EPA)
Plumes of mist over the partially frozen Niagara Falls. (Rick Warne / EPA)
A rainbow adds a slice of color at Niagara Falls. (Rick Warne / EPA)
Extreme cold brought new beauty to the falls. (Rick Warne / EPA)
