Hilary was a rare storm. Here's why

One name has been on millions of minds — and all over the news — in the past week: Hilary.

It's been decades since a storm like Hilary has hit Southern California, so even some scientists were shocked when they heard it was coming.

"My response was, 'What?' Just sort of, 'Really? This is happening?'" says Jill Trepanier, an associate professor of geography and anthropology at Louisiana State University. Trepanier studies extreme climatic and weather events, like tropical cyclones.

In today's episode, Regina Barber talks to Trepanier about how scientists predict events like this, and what Hilary and future storms may or may not tell us about the changing climate.

The storm started as a hurricane off Mexico's Pacific coast. By the time it hit California on Sunday, it had been downgraded to a tropical storm. As it continued to move inland towards Nevada Monday morning, Hilary was downgraded again to a post-tropical cyclone.

In the end, Trepanier says, it takes more than one unusual event for researchers to put together a pattern that is attributable to climate change.

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This story was produced and fact-checked by Rachel Carlson. It was edited by managing producer Rebecca Ramirez. The audio engineer was Patrick Murray.