The National Weather Service estimated that 16 twisters landed across North Texas, and some of them were EF-4 tornadoes. What does that mean?

It should be warm this weekend, May 17-19, for Washington, D.C., though we might see some rain showers or thunderstorms, according to forecasts. No matter what the weather, though, there's lots going on in and around D.C. -- read on for details.

As if the backing of NASA, 18 independent American scientific societies, and an intergovernmental panel established under the United Nations weren't enough to quell the protests popping up in comment sections across the Internet, a new study published in the journal Environmental Research Letters confirms — once again — that climatologists almost unanimously believe that climate change is directly related to human-made carbon emissions.

Officials with the National Weather Service (NWS) have determined the strength of several tornadoes that touched down across North Texas Wednesday night. As of Thursday afternoon NWS officials estimate that 12 tornadoes touched down.

Severe weather led to $216 million in catastrophe losses in April for Allstate Corp., the insurer said Thursday. Two severe weather events accounted for more than 75 percent of the estimated loss for the ...

A line of deadly thunderstorms struck North Texas late on Wednesday, dropping giant hailstones and a series of tornadoes that leveled whole subdivisions. Six people were killed and as many as 14 were still missing as of Thursday morning. 

For information about loved ones, to locate a shelter in the areas affected by severe weather, or to make a donation, visit our storm resources page.

By Lawrence Hurley and Valerie Volcovici WASHINGTON (Reuters) - With a barrage of legal briefs, a coalition of business groups and Republican-leaning states are taking their fight against Obama administration climate change regulations to the U.S. Supreme Court. The U.S. Chamber of Commerce and other industry groups, along with states such as Texas and Virginia, have filed nine petitions in recent weeks asking the justices to review four U.S. Environmental Protection Agency regulations that are designed to cut greenhouse-gas emissions. ...

By Tom Brown MIAMI (Reuters) - The U.S. National Weather Service is getting a quantum jump in computing power that will significantly improve its forecasting and storm tracking abilities to better protect the country from severe weather. "This is a game changer," Louis Uccellini, who took over as director of the National Weather Service in February, told Reuters in an interview, calling it "the biggest increase in operational capacity that we've ever had. ...