Ian is now considered a post-tropical cyclone. What does that mean for NC?

After Ian made landfall in South Carolina Friday afternoon, national weather officials eventually downgraded the storm from a hurricane to a post-tropical cyclone.

What does that mean? That’s different from both a hurricane and a tropical storm.

But officials warn that no matter the name, the storm can still have a powerful impact on land with wind gusts and heavy rainfall, which could lead to flooding and downed trees.

Here’s a look at these terms.

What’s a post-tropical cyclone?

A post-tropical cyclone is a cyclone that no longer possesses sufficient tropical characteristics to be considered a tropical cyclone, the National Weather Service says. But post-tropical cyclones can continue to carry heavy rains and high winds.

Tropical cyclones develop over warm tropical oceanic waters, and they have a spiral or circular system of strong winds rotating around an eye, which is sometimes hundreds of miles across in diameter, according to the Red Cross.

What’s a tropical storm? What’s a hurricane?

A tropical storm is a tropical cyclone with maximum sustained winds between 39 and 74 mph, according to the National Oceanic and Atmospheric Administration.

As soon as maximum sustained winds reach 75 mph or higher, the tropical cyclone is categorized as a hurricane. (And major hurricanes have maximum sustained winds of 111 mph or higher.)

Ian’s wind speeds

Ian had maximum sustained winds of 70 mph Friday afternoon, per the U.S. National Hurricane Center.

Ian hit Florida’s Gulf Coast Wednesday as a powerful Category 4 hurricane with 150 mph winds.

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