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Forecasters Predict Active Hurricane Season

May 16, 2005

BAY ST. LOUIS, Miss. (AP) — The Atlantic Seaboard and the Gulf Coast of the U.S. could be in for another bad hurricane season, one of the government’s top forecasters reported Monday.

Conrad C. Lautenbacher Jr., head of the National Oceanic and Atmospheric Administration (NOAA), predicted 12 to 15 tropical storms, seven to nine of them becoming hurricanes, and three to five of those major hurricanes, with winds of at least 111 mph.

“We can’t predict this far in advance how many will strike land,” he said. But given the active season, “be prepared for two or three of these to make landfall.”

On average, the United States is hit by two major hurricanes every three years.

Last year, there were 15 tropical storms, with nine of them hurricanes – six of them major. Florida got hit by an unprecedented four hurricanes.

Lautenbacher said the 2005 forecast was based on a large number of factors, including air pressure, winds and surface temperature.

Forecasters at Colorado State University have also predicted a significantly above-average Atlantic hurricane season. In April, William Gray and his team said they expect 13 named storms, including seven hurricanes, three of them major.

The hurricane season begins June 1 and runs through Nov. 30.

Hurricane Forecasters Relying on Public

Until the evening of Aug. 13, the National Weather Service’s forecast office in Melbourne had no need for an alarm warning central Floridians of dangerous winds. After all, it had been 44 years since a hurricane stuck the region.

But with Charley bearing down on one of the state’s most populous regions, meteorologist Dennis Decker and two other supervisors were pressured to think of a way to grab the public’s attention before disaster struck.

If they sent out another update, it risked being lost amid the flurry of bulletins coming from their office and the National Hurricane Center. Yet, if they didn’t do anything people could be caught unprepared.

“We ended up using a wrench for a hammer,” said Decker, the Melbourne office’s warning coordinator.

At 6:42 p.m., they issued a tornado warning, which immediately sounded alerts in newsrooms across the area. But there was no twister. Instead, the National Weather Service was getting out the word that Orlando had a half-hour to prepare for the eyewall’s 100-mph winds.

As Florida prepares for the 2005 hurricane season, which runs from June through November, experts know disseminating forecasts is just as important as accurately predicting storms’ paths. And it’s just as crucial that Floridians listen.

“Even if I tell you you’re going to have a hurricane and the forecast is perfect, if you’re not paying attention you’ll may never know,” said Lixion Avila, the senior forecaster at the National Hurricane Center in Miami.

The inability to effectively warn inland regions of the wind was just one of the weaknesses exposed in 2004 by the four hurricanes that lashed Florida, killing 130 and causing an estimated $22 billion in insured damage.

Hurricanes Charley, Frances, Ivan and Jeanne showed that experts’ predictions are inexact – and can be made worse by the public’s confusion. Even the best hurricane forecast is useless if it never reaches people, or doesn’t clearly describe the “where” and “when.”

That’s where the quick thinking by Decker and his peers comes in.

“When you do something outside of the box like that, you wonder how the people up the chain (of command) in the Weather Service are going to react,” Decker said. “They basically confirmed it was a good idea.

“In fact, it will be written into the operations plan for this year that under similar circumstances, until the weather service comes up with a specific product for that situation, we’ll be able to do that.”

It is cruical for weather service offices to issue timely warnings because they provide the forecasts for specific areas, essential for county and local emergency officials. Meanwhile, the hurricane center is more concerned with general information about the hurricane.

This offseason, the hurricane center thought another good idea would be a re-examination of the forecast map it presents to the public.

The closer Charley came to the mainland, the more that people grew fixated on the graphic showing the experts’ best guess on the path of the hurricane – a black line studded with dots, projections of the storm’s center. The morning of that fateful Friday the 13th, the line stabbed directly into Tampa Bay.

But what went ignored was the white “cone of uncertainty” over the black line, indicating the potential track area. So, when Charley took a slight turn to the east in its final hours before landfall, many southwest Florida residents were caught off-guard despite the graphic’s warning they might be in danger.

“We didn’t tell anybody the center is going to go to Tampa or the center is going to go to any other place,” Avila said.

This winter, the hurricane center came up with two alternatives: the cone and dots, without the line; and colored circles indicating the margin of error inside a cone. After surveying the public, including emergency officials and meteorologists in the media, the experts decided to keep the line because it was judged to be the clearest way to show a projected path while still indicating the margin of error.

One new development is an experimental graphic showing the probability of hurricane- and tropical storm-force winds over inland regions. Like Decker searching for a way to sound an alarm, this was something the hurricane center lacked.

“The forecast (for Charley) was good,” Avila said. “But it’s the way we tell the people.”

As Avila boasted, the forecasts are good – and getting better. The mean error for a three-day forecast was more than 300 miles as of 20 years ago; now, it’s about half that.

Still, there are limitations, such as delivering an accurate forecast of a storm’s strength. Charley, in the 10 hours before making landfall in Charlotte County, blossomed from a Category 2 hurricane (sustained winds of 109 mph) to a strong Category 4 (150 mph sustained winds).

“That’s the nightmare of a hurricane,” Avila said. “With the technology and present information we have, we do not know how to forecast those rapid changes in intensity.”

To improve predictions of hurricanes’ strengths, a team of outside experts is being gathered to review the National Hurricane Center’s research and development efforts.

The 2004 season was a learning experience for all Floridians, who found out the hard way that no part of the state is safe. The storms’ unpredictable paths can take them through regions historically untouched, such as northeast and central Florida, while their immense size can produce rainbands roaring through areas hundreds of miles away from the eye.

The hurricane center conducted an outreach campaign this winter, spreading the word on how to understand a forecast. Everyone will know by Thanksgiving whether that effort saved lives and property.

“The battle is won during the offseason,” Avila said. “You can’t do anything once the hurricane is here; you have to prepare people well in advance.”

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On the Net:

National Hurricane Center/Tropical Prediction Center: http://www.nhc.noaa.gov/

National Weather Service Forecast Office – Melbourne: http://www.srh.noaa.gov/mlb/


Forecasters Predict Active Hurricane Season


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