Michelle Obama celebrates 50th birthday in Hawaii as US shivers
The First Lady is avoiding the coldest US weather in decades by remaining in Hawaii without Barack Obama or their daughters.
She had opted to take an extended winter break with friends ahead of her 50th birthday on Jan 17, officials said.
President Barack Obama and their two daughters, Malia and Sasha, stepped back on to an icy White House lawn yesterday morning as Arctic conditions gripped much of the United States.
A "polar vortex" of freezing air is descending from the North Pole and is expected to push south as far as as normally balmy Florida.
Officials warned that some 140 million people, almost half of the American population, will face subzero conditions in 20 states over the coming days.