A major storm is lashing California with powerful winds and is set to deliver months’ worth of rain that could trigger debris flows and flash floods.

Cold and snowy weather has gripped much of the northern tier of the United States since Thanksgiving, but a pattern change will torch the chance of white Christmas for many.

(CNN) — High above the North Pole, in a slice of atmosphere rarely noticed and even less understood, a transformation is underway. Over the next 10 days, changes in the stratosphere will upend weather ...