ASU climatologist discusses impact of Hurricane Hilary

Hurricane Hillary was the first tropical storm to hit Southern California in 84 years.

ASU Climatologist Randy Cerveny explained to us how Hilary impacted Arizona weather.

“Yuma, only gets around three inches of rain the entire year and they got a substantial portion of that just within the last 48 hours,” Cerveny said. “If you compare those numbers to places back east it doesn’t seem that much, but our soil doesn’t handle that very well. When you dump that kind of rain on sand and clay, it doesn’t go anywhere and you get flooding.”

Hilary dumped massive amounts of rain and brought flooding to parts of California, that led to numerous rock and mud slides.

The National Hurricane Center in Miami downgraded Hilary to a post-tropical storm Monday morning. But the storm hit California hard over the weekend.

“To have a storm at tropical storm strength make landfall in the United States, and it did when it was crossing into California, that is extremely rare,” Cerveny said.

Tropical storms as strong as Hilary aren’t typically seen in the West Coast however, as climate change progresses, water temperature heats and wind currents change, it makes storms like this possible.

“Warm waters are the duracell batteries of a hurricane, you keep a hurricane over warm water it has chance to get bigger,” Cerveny said.

Seeing the storm maintain strength and reach the West Coast shows how sea surfaces temperatures have warmed due to climate change, which can impact the climate in Arizona.

“The fact that we’ve already had in August a tropical storm work it’s way up Baja, and remember it doesn’t really get it’s act together in September/October we’re going to have more of these,” Cerveny said.