In a test that starts Monday, five weather service offices in Kansas and Missouri will use words such as "mass devastation," "unsurvivable" and "catastrophic" in a new kind of warning that's based on the severity of a storm's expected impact. The goal is to more effectively communicate the dangers of an approaching storm so people understand the risks they're about to face.

It's not just the "Tornado Alley" any more. Tornadoes are striking in more parts of the U.S., more often, a new study shows.

Experts are enlarging the area of the U.S. they believe is regularly in the path of severe storms, tornadoes, and hail damage, according to a report from CoreLogic.