Storm clouds are seen on the east coast of the United States in this NASA handout satellite image taken at 1415 GMT, December 25, 2012. A strong winter storm was expected to bring a white Christmas morning to millions of Americans Tuesday - but also high winds and even the risk of tornadoes for some.
Credit: Reuters/NASA/NOAA/GOES Project/Handout
Credit: Reuters/NASA/NOAA/GOES Project/Handout