Forecasting The 2009 Hurricane Season

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LYNN NEARY, host:

The Atlantic hurricane season began June 1st and runs through the end of November and so far, nothing. It's the quietest start to the season in 17 years. You can thank El Nino in part. But there's still a long way to go. And historically, some of the fiercest storms landed after early August.

In just a moment, Bill Read, the director of the National Hurricane Center, will join us to talk about the storm season so far, and what we might expect and what we should do to prepare for hurricanes and other tropical storms.

If you'd like to talk with the director of the National Hurricane Center, give us a call especially if you live near the coast. The number: 800-989-8255. And the email address is talk@npr.org. Joining us now from WLRN, our member station in Miami is Bill Read, director of the National Hurricane Center. Good to have you on TALK OF THE NATION.

Mr. BILL READ (Director, National Hurricane Center): My pleasure.

NEARY: So, it's been a slow year so far, as we just said. Why is that?

Mr. READ: Well, it's - I think it's somewhat of a perceptional thing. We've been in an active pattern since the mid '90s, so we're used to having perhaps a lot more activity early in the season. But over the history that we have, the climatology on hurricanes, the average data of the first storm to reach hurricane strength is August 14th. And generally speaking, there's one or two named storms formed before early August, so we're not that far into the peak of the season yet to be saying it's a really slow season. A lot could happen between now and the end of October.

NEARY: Well, what does El Nino have to do with hurricanes and the way they develop?

Mr. READ: The most common effect of an El Nino is to - it's a warming out in the Pacific. And for most people, say, now, what the heck does that got to do with the Atlantic Ocean way far away? But when the oceans are warm in the tropical Pacific, you get a lot more thunderstorms out over that area and that brings air up into the upper levels of the atmosphere. And through some interaction with the overall flow, ends up with a increase in a westerly component of the wind over the Caribbean.

And wind shear is anathema to hurricane development. So, when the jetstream or the higher winds aloft are going from west to east across the Caribbean, we don't see development there. And that's pretty much the way it's been this year. There's been little or nothing in the Caribbean to look at.

NEARY: Now, I understand there is a storm brewing that may be the first named storm of the year, is that right? Or what's happening? What's brewing?

Mr. READ: Okay. Over the last week or so, the open waters of the Atlantic, almost on schedule, the so-called Cape Verde season, the waves coming off of Africa showed a little more character than earlier in the season. And we've had - we have a depression right now that's about a the third of the way across from the Cape Verde islands to the Caribbean islands. That hasn't shown - in fact, it's actually weakened since it first developed and may or may not hold together. We're still watching on that one.

And then, a secondary way - another way it came off behind that one and it came off of Africa yesterday and we're currently - carrying it just south of the Cape Verde islands, and are carrying a high risk of that one becoming a tropical cyclone in the next day or so.

NEARY: So, I want to ask you to just remind us what El Nino is. We were talking about El Nino before, but maybe some people don't know what El Nino is.

Mr. READ: Mm-hmm. El Nino is a - is named for an oceanographic phenomena where the tropical waters in the Pacific Ocean end up in a long band along the equator in north and - just north and south of it to be a little bit above their normal average which disrupts the weather patterns pretty much around the Pacific Basin and some carryover with impacts into the Atlantic area. Mainly, it's manifested in winter with storminess in our West Coast, draught off of - in parts of South America, shuts downs the rainy season in the Caribbean, for example. And that's the primary thing with El Nino.

NEARY: One other question about language. We're talking about the hurricane season, but we know that Taiwan and parts of Asia had been devastated by a typhoon. What is the difference between a hurricane and a typhoon?

Mr. READ: Name and where it formed. A typhoon is a name that mostly anglicized from a Japanese definition of tropical cyclones. But that's the name given to the systems that do form in the western Pacific, from Guam westward on into Asia. There's usually - on the order of twice as many storms in a season -that's the most active basin around the globe. And their season really never ends. They occur in any month of the season.

NEARY: But as storms, they're basically the same then, you're saying?

Mr. READ: Sure. The physical mechanism of a typhoon is identical to a hurricane.

NEARY: Yeah. Now, how do you predict where a hurricane will go and what's going to happen to a hurricane?

Dr. READ: Well, the key - the key function is first, one of the difficult tasks is to get one of these - when we get a tropical wave of which there may be somewhere in the order of a hundred areas of disturbed weather that we call tropical waves during the hurricane season. And we have an average season say of somewhere between, in the active period we're in now, 11 and 14 say storms out of about a hundred. Now we've got to figure out which ones are going to develop. Once we've gotten a developed system, the process is the forecasters do a very intense diagnosis of the system. How big is it, how strong is it, exact locations?

That information gets fed into our evermore complex and powerful computer models that we're able to run and that becomes the backbone of the forecast system. We diagnose, the models run on a set of guidance for us, we interact with that guidance and then produce a forecast which now goes out to five days where we have skilled - measurable skill on the track forecast. And to some extent in the intensity, though we still have a long way to go on that.

NEARY: Bill Read is the director of the National Hurricane Center. If you'd like to join our conversation, the number is 800-989-8255. We're going to take a call now from Ed(ph), who is calling from Parkland, Florida. Hi, Ed.

ED (Caller): How are you doing?

NEARY: Good, thanks.

ED: I just, you know, my house was built in 2003 and the hurricane panels when I put them up, especially on the second story, it locks my family in the house. And if there's a fire, unless they go down the stairs, they're not getting out. And I didn't know what type of enforcement or what type of rules apply here to, you know, I just was curious what you do to get out of your house, when you put the…

Dr. READ: Yeah, that's an issue. In fact, that would be a question I would probably bring your experts in the fire department out and suggest because it would be unique probably for every house what the safest way to do that on. Myself, personally, I was in a one story house and I left - a doorway is the last element to be closed off for the storm. So, I had that way of egress.

NEARY: So, Ed you're saying you would put the panels up once the storm began but then that would lock you in, is that what you're saying?

ED: Yes, and if there's another hurricane, which happened a couple of years ago. It was coming a couple of days later - you know, I left them up and because it's, you know, hard getting on the ladder, taking them off and on, so I left them up along with the rest of my neighborhood. But, you know, the only way out is to get to those stairs, get down them and out the front door.

Dr. READ: Here's - here's what I would - if I was in a two story house with my family and I had the panels up I would make it a camping trip and stay on the downstairs. Two reasons. One, the fire issue that you recognize. The second is, the wind - the affect of the wind is - increases as you go up due to less friction. So, you're going to be better protected on your lower floors than your upper floors. You're safer in your lowest floor of your house in the event of the wind.

NEARY: All right. Thanks so much for your call.

ED: Thank you very much.

NEARY: Okay. We want to take a call from George(ph), who is calling from Gainesville, Florida. Hi George. Are you there?

GEORGE: Hi, thanks for taking my call. I just had a question to Dr. Read about the hurricane prediction forecast. And it's really more of a concern. It seems like, maybe not a lot of good seems to come from it. It doesn't appear that it's very correct every year, it has to be adjusted. And even when it is close, I don't know all the positives there are to gain from it. One of the biggest negatives that you see are the amount of - to a state like Florida or even a place more the Keys, where if they hear an unusually high number of storms being predicted, they may steer clear of vacationing in these areas that rely on tourism.

And I just wanted to hear your thoughts about it because I think there's other ways you could inform the public about being prepared for hurricanes other than making these predictions that don't ever really seem to be correct.

Dr. READ: Well, there are several points to that question. I'm personally not the greatest fan of seasonal forecasts for a different reason. I think people take them as too explicitly as they are. And in fact, we at the hurricane center aren't the initiators of those.

GEORGE: Right.

Dr. READ: Our area of expertise is on the short term. And, I did a little bit of sort of informal research sniffing around. I have not seen the reduction in predicted active years and people taking trips. In fact, I haven't even seen a whole lot of reduction when there's active weather going on and people taking trips. But what I'm more concerned about is when I hear officials, elected officials or - and whatnot actually say, looks like we're going to have a quiet season. And then I have to go and remind them that 1900 was a quiet season and it wiped out Galveston. In 1992, in fact…

GEORGE: Right, hurricane.

Dr. READ: …was later than this year and it was Hurricane Andrew. So, the number of storms has no correlation with landfall and impact in the United States. So, the main thing I use this for is since it's out there, you're not going to take it away. It's a very potent entertainment value, the media are all over it and quite a few people are putting them out. So they're not going to go away. And I do use that to emphasize the fact that it only takes one.

NEARY: All right, thanks so much for your call, appreciate it.

GEORGE: Okay.

NEARY: We're going to take a call now from Drew(ph) in Charlotte, North Carolina. Hi, Drew.

DREW (Caller): Hello.

NEARY: Hi, go ahead.

DREW: Hi, thanks for taking my call. Dr. Read, I was wondering if you could speak a little bit to the most damaging aspects of hurricanes that you get. I mean, I know we have storm surges, there's wind, there's rain. Is there any one of those in particular that tends to be the most damaging factor of the hurricane on average? And, you know, what are some of the best tactics you can use to keep your house safe from those damages?

Dr. READ: Well, from a dollar damage point of view over time, wind has been the number one culprit on there. But it is actually storm dependent. You can have -for example, tropical storm Allison in 2001 was a minimal wind event. There was virtually no wind, no surge, yet several billion dollars in damage occurred from fresh water flooding. Flip the coin, you have Andrew which was tens of billions of dollars damage primarily due to wind. Then you have Katrina and Ike in very storm surge prone areas where there was quite a bit of surge damage.

Surge, the only known way to protect from that is to not build in the surge zone. And we do that with regularity. With wind, a lot has been learned on how to build to increase the resistance to wind of a house. It's very effective if used in a new house being built now. And Florida has a code that allows for that. And if it's done properly, will go a long way to protecting your family and your property inside. Other states not so well yet. But that is the number one way to do that.

Pre-existing houses, if you can cover your windows with good certified shutters that will prevent the wind from getting in, you've significantly increased its integrity in the event of a hurricane. Now that's the number one thing that you can do to protect your house. One thing I would recommend…

NEARY: Bill Read is the director of the National Hurricane Center. And you are listening to TALK OF THE NATION from NPR News. And we're going to go to Honolulu, Hawaii now, Rose(ph). Hi, Rose.

ROSE (Caller): Hi. Yes my question is, we just had a near brush with Hurricane Felicia, fell apart on our doorsteps. But, do you think our state is more susceptible with global warming and El Nino happening. Thank you.

Mr. READ: Yeah…

NEARY: Thank you for calling.

Mr. READ: …the studies by climate modelers is somewhat inconclusive on just how much impact the climate change is going to have on the frequency and strengths of hurricanes. And more on the order of - in how much the magnitude will change. The going process right now is that there will be no more, maybe even less in numbers over a long period of time and slightly stronger storms. But nothing alarmingly different. I think a more important impact to concern yourself on coastal areas and islands is how much of a sea level rise eventually occurs or not depending on the degree of climate change and the effect on the polar regions.

NEARY: You know, we've been hearing obviously from people who live near the coast. But, if you live inland, how much do you have to worry?

Mr. READ: Well, that's where the number one threat becomes - I mean, there is wind, loss of power, tree limbs coming down and the like. But the number one challenge for the inland locations is the torrential rains and the loss of life that occurs from the flooding of that. For example, what just happened over in Taiwan with Hurricane Camille. Forty years ago, as many people lost their lives in Virginia to flash flooding as on the coast.

NEARY: So, the people inland have to pay attention to these warnings as well. Bill Read, thanks so much for being with us today. Bill Read is the director of the National Hurricane Center. And he joined us today from member station WLRN in Miami, Florida.

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