The sirens sound when the skies turn black and violent supercell thunderstorms roar through.

Three locations in Boulder, Broomfield, will showcase lab tours, aircraft, scientific tools large and small, and conversations with staff.

The difference between El Niño and La Niña can be a huge one for U.S. weather and for global climate. A strong El Niño can nudge global temperatures upward for up to a year.

A study led by NCAR visiting scientist Erich Fischer analyzes regional climate simulations to project where heat-wave-related health risks will increase in Europe as Earth’s climate warms.

The year 2010 brought a difficult and sometimes tragic few months of weather events—first the snowstorms and record cold that battered much of the Northern Hemisphere, then tornadoes and floods in the United States.