Governors across the southeastern United States have declared statewide states of emergency as Hurricane Helene continues its ascent. After forming in the northwestern Caribbean Sea Tuesday, Helene escalated from a tropical storm, then to a cyclone, and finally to a Category 4 hurricane by the time it made landfall late Thursday night. We talk to hurricane climatologist Jill Trepanier about how a storm tropical storm system rapidly intensifies into a major hurricane, the impact of a changing climate on future storms — and why the devastation doesn't stop at the shore.Follow local updates on Hurricane Helene.Want to know more about the scientific underpinning of serious weather events? Email us at shortwave@npr.org — we might cover it on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy