The world of severe storm science was shaken by the deaths of three longtime researchers in a vicious tornado on May 31. The storm also raised serious questions about how urban dwellers can best respond to tornado threats.

NCAR has made key upgrades to its Helicopter Emergency Medical Services tool, which helps helicopter rescue pilots decide quickly whether weather conditions are safe enough to attempt a low-altitude flight.

Carbon dioxide concentrations in the atmosphere have crossed a major threshold: 400 parts per million. Here are five key points on how carbon dioxide is affecting Earth’s atmosphere and the role we're playing in it.

To better predict where thunderstorms will rip across the central United States this spring, researchers are teaming a high-flying aircraft with fine-grained computer simulations.

The last month has seen a trail of smashed records across the central United States, as pulse after pulse of cold air careened down the Great Plains. How does this fit into the bigger picture of a warming U.S. climate?