tampabay.com

Hanging onto skinny line

The hurricane center plans to discourage obsession with it by using a color-coded map that displays the odds a storm will hit.

By Times Staff Writer
Published May 29, 2005


The skinny black line lives.

The National Hurricane Center took some heat in August 2004 when Hurricane Charley veered off its forecast path and slammed into Port Charlotte. Much of the criticism centered on the black line that represented the predicted path of the hurricane.

"We've got to do everything we can to keep people from overly focusing on that line," Max Mayfield, the center's director, said in November. So in the off season, the hurricane center went looking for possible alternatives.

But in March, center officials announced the line will stay. A majority of the weather center's users, it turns out, like the skinny black line.

"Our users made it clear: "Leave it alone!' " said Scott Kiser, tropical cyclone program manager for the National Weather Service.

The weather service solicits feedback from its users when it might make a major change to one of its products.

The service put up two alternatives for consideration:

The first would have deleted the black line but kept the cone that represents the predicted danger zone. The other displayed a variety of circles showing the forecast for different time periods. For instance, a circle would show where the storm might be in 24 hours, then in 36 hours, and so on, without a line.

The original map, the one with the black line, received the approval of 63 percent of the nearly 1,000 scientists, emergency workers and media representatives who responded to the request for feedback. Neither of the two alternatives received more than 24 percent approval.

"People seemed to want all the information they could get," Kiser said. "They knew that the line was just a forecast, not an absolute guarantee."

Weather service officials also examined newspaper editorials, letters to the editor and feedback from town meetings before deciding to keep the line, Kiser said.

The skinny line first appeared in 2002 at the request of weather watchers and scientists who wanted the center to draw its best guess of a storm's path.

Hurricane center officials have frequently urged against obsessing over the black line.

Hurricane center director Mayfield joked during the busy 2004 season that he would have his tombstone engraved with the words: Don't focus on the skinny line.

Hurricane Charley was a case in point. Port Charlotte, where it hit, was within the parameters of the projected cone for Charley, even though the storm was originally forecast to hit the Tampa Bay area.

But too many people focused on the skinny line.

"Hurricane Charley was a major wakeup call for people," said Randy Rauch, meteorologist at WTSP-Ch. 10. "It showed that hurricanes are still very unpredictable."

Even the cone does not always accurately predict a hurricane's path. In fact, it can be wrong as much as a third of the time, one study showed.

"We have to continue to educate residents that the weather service doesn't issue guarantees. They are best guesses," said Gary Vickers, Pinellas County's emergency management director. "The line is not the whole story."

The hurricane center plans to use another tool to help discourage residents from relying too much on that black line: a color-coded map that displays the odds that hurricane or tropical-storm force winds will hit an area.

For instance, a day before landfall, the odds of Charley's core hitting either Tampa or Port Charlotte were the same, about three in 10, according to the hurricane center.

The map will also include predictions on a storm's size and intensity. The center plans to post the map on its Web site.

Kiser advised that anyone living anywhere near the path of a hurricane remain alert and ready for changes in the forecast, no matter what the maps indicate.

"We are not likely to issue a perfect forecast," he said.

Information from the Associated Press was used in this report.