A worker photographs a tree that fell on power and fiberoptic lines and blocked a highway in Washington state on Tuesday. Ted S. Warren/AP hide caption
National Weather Service National Weather Service
A man makes his way through floodwaters in a parking lot on Isle of Palms, S.C., on Monday. Mic Smith/AP hide caption
Purdue University students are testing new software that may track and warn about tornadoes, such as this one which struck Rochelle, Ill., in early April. Walker Ashley/AP hide caption
Mark Kunze of San Bruno pushes his stalled vehicle out of a flooded intersection Thursday in South San Francisco. Alex Washburn/AP hide caption
A map by the National Weather Service predicts winter weather spreading through the north-central U.S. Monday, and spreading east. National Weather Service hide caption
A car is abandoned on a flooded street following heavy rains and flash flooding in Bay Shore, N.Y., on Wednesday. The South Shore of Long Island along with the tri-state region saw record-setting rain that caused roads to flood. Andrew Theodorakis/Getty Images hide caption
Data released Tuesday shows that the deadly El Reno tornado that struck Friday was the widest every recorded in the U.S., at 2.6 miles. National Weather Service hide caption
Two women look for a taxi in New York's Times Square on Friday. AFP/AFP/Getty Images hide caption
Current winter storm watches and warnings from the National Weather Service. National Weather Service hide caption
Jan. 21, 2012: A winter scene in Brooklyn, N.Y. Snow may be a relatively rare sight this coming winter in the U.S. Spencer Platt/Getty Images hide caption
Doug Jones, owner of Piedmont Biofarm in Pittsboro, N.C., waters vegetables as temperatures in the South soar, Friday, June 29. Triple-digit temperatures are expected for several days in North Carolina. Gerry Broome/AP hide caption
Branches and power lines littered the nation's capital after bruising storms swept through the Mid-Atlantic region on Friday night. Win McNamee/Getty Images hide caption
The darker areas are being warned about what's coming. They're where tornadoes could occur on Saturday and into Sunday. Storm Prediction Center hide caption
Nine-year-old Maddie Meek (L) and her mother Dina Meek salvaged what they could from a relative's home in Joplin earlier today (May 24, 2011). Joe Raedle/Getty Images hide caption
