Brutal cold snap hits U.S.

Much of Dallas is coated in ice. The ice storm that has hit northern Texas has left more 250,000 residents and businesses without power and has led to more than 1,700 flight delays and cancellations across the country.  (Ronald Martinez / Getty Images)

City of Richardson employees Dickie Cooper, left, and Nate Griffith use chainsaws and other light equipment to cut up a fallen tree blocking a neighborhood intersection. An ice storm in North Texas has knocked out power to more than a quarter of a million homes and businesses, canceled almost 1,000 flights and contributed to a fatal wreck.   (Tony Gutierrez / Associated Press)

This image released by the NASA GOES Project shows a storm crossing the Midwest. Ice, snow and freezing weather are part of the winter storm that stretches from the Texas-Mexico border to the Ohio Valley. Forecasters are reporting it as one of the worst to hit the U.S. in recent years, snarling travel on the ground and in the air and knocking out power for hundreds of thousands of people.  (NASA via AFP/Getty Images)

Lauren Roberts, left, and her friend Croline Brooks enjoy the frozen conditions at Hoblitzelle Park in Plano, Texas.  (Stewart F. House / Getty Images)