Interview between Ari Shapiro and Bryan Norcross
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Shapiro: Why does the category of a hurricane consider only wind speed and not water?
Norcross: Because we can measure the wind speed very reasonably well, and we can measure the pressure of the storm. But what we don't know is how the rainfall or the storm surge, which is the ocean being pushed up over the land, is going to interact with the particular land area that the hurricane is going to hit. For example, Hurricane Florence would have had a significantly different effect on Florida than it did in North Carolina because the coastline is different, the terrain is different. So it's just impossible, really, to put a number on the storm that will tell us how bad it will be when it interacts with the land because the land is such a big player in that.
Shapiro: Do you think that in North Carolina there were people who wound up in harm's way because they said to themselves it's only Category 1 even though at the same time everyone was saying this is going to be a rain event, not a wind event, there will be flooding, get out?
Norcross: I think absolutely that happened. People that waited saw the storm - the wind speeds lower in the storm and they stayed. But what's happened is as more and more meteorological information has come out over the years, people pay more attention to the meteorological information and less attention to whether evacuations have been ordered for specific areas. And I'm talking about in places that are generally populated. And the most important safety information is, am I ordered to be evacuated or not? And that information is so often these days muddied by spaghetti plots and cones and models and projections of wind speeds and all those things when what we know is that even Category 1 hurricanes can be disastrous.
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