As millions of Americans hunker down for the winter storm, 19 states and Washington, D.C., have declared states of emergency.

Multiple tornado warnings hit Oklahoma early Thursday as a line of severe thunderstorm systems moved in. The first warning came during morning commutes and school drop-offs, with visible damage ...

Add Yahoo as a preferred source to see more of our stories on Google. Multiple tornado warnings hit Oklahoma early Thursday as a severe storm moved in. The first warning came during morning commutes ...

Multiple tornado warnings hit Oklahoma early Thursday as a line of severe thunderstorm systems moved in. The first warning came during morning commutes and school drop-offs, with visible damage ...