Update From The National Hurricane Center

LULU GARCIA-NAVARRO, HOST:

Hurricane Irma is closing in on mainland Florida. It's now a Category 4 storm with sustained winds near 130 mph. During the next 24 hours, this storm is likely to affect the entire state from the Keys to Tallahassee. NPR's Jon Hamilton is at the National Hurricane Center in Miami just down the street.

Good morning.

JON HAMILTON, BYLINE: Good morning.

GARCIA-NAVARRO: So fill us in. Where is Irma right now?

HAMILTON: Well, I'm looking at the big screen here at the Hurricane Center, and it looks like the eye of the storm is just east of Key West. The storm is moving pretty slowly right now, about 8 mph. And it's expected to pick up speed later on today. So forecasters here think Irma is going to hit the southwestern tip of Florida in the next few hours - that's the area around the Everglades National Park where there aren't many people. But after that, it's going to head up the west coast of Florida, and that's going to take it past a lot more populated areas, like Fort Myers. And looking ahead to tonight and tomorrow, Irma is likely to head for Tampa. And then it should begin to weaken as it heads inland toward Georgia.

GARCIA-NAVARRO: Yeah, Irma is less powerful than it was a couple of days ago, though. But it's still a very large, very dangerous storm, right?

HAMILTON: This storm is really, really big. It's more than 400 miles across. So when you look at it on the monitors here, it spans the entire Florida peninsula. And in fact, forecasters here have issued hurricane warnings for both the east and - east and west coasts of the state. It's just kind of amazing. And because this storm is so massive, a big chunk of southern Florida has been feeling these intense bands, as I'm sure you know. Wind and rain...

GARCIA-NAVARRO: Yes.

HAMILTON: ...For many hours now. And it's been pretty intense. The hurricane center here actually shut its steel outer doors last night. That was when the winds started to reach tropical storm force. And we're hearing it's going to be quite a few more hours before those doors get opened again.

GARCIA-NAVARRO: Yes, so you are indeed on lockdown. What is the greatest threat from Irma?

HAMILTON: Well, of course, the wind is really scary. I mean, 130 mph gusts - you know, that's enough to rip the roof off of a house. That can uproot a tree. And forecasters here are saying Irma is probably going to spin off tornadoes, as well. So that could mean even higher wind speeds in some local areas. But the big risk from this storm is really water, not wind. The storm surge along the west coast of Southern Florida is going to be 10 to 15 feet above normal tide levels, they think, at least in some places. And, also, Irma is expected to drop more than 20 inches of rain in some places. So you have this combination of storm surge and torrential rain, which could be really just deadly for anybody who's in a low-lying area. And, of course, the damage to homes could be incredibly costly.

GARCIA-NAVARRO: Very briefly, Irma is heading towards Tampa. They were not expecting it. What's the impact going to be like there?

HAMILTON: It has the potential to be pretty bad. I mean, forecasters here are saying the area around Tampa Bay could get a storm surge of 5 to 8 feet - that's less than down South. But it's scary because Tampa and St. Petersburg are among the most vulnerable cities in the U.S. when it comes to flooding. I mean, fortunately, they haven't been hit by a major hurricane in nearly a century, but there are hundreds of miles of coastline around Tampa Bay. A lot of that land is just a few feet above sea level, and sea level has been creeping higher for decades now, thanks to sea level rise.

GARCIA-NAVARRO: That's NPR's Jon Hamilton at the National Hurricane Center here in Miami. Keep safe.

HAMILTON: Thanks.

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