MIAMI – Congratulations. The hurricane season – a surprisingly gentle one – is effectively over. Now, experts say, use the breather wisely and don’t take too much for granted.

After two brutal seasons, the law of averages kicked in this year and the gods of wind and rain treated us kindly, but scientists say the long-term outlook remains stormy.

We still are locked in a decades-long period of heightened activity, they say, and should not be misled by the relatively benign 2006 hurricane season, which officially ends Thursday.

“I am so thankful that someone decided to give us a break,” said Stanley Goldenberg, a researcher at the National Oceanic and Atmospheric Administration’s Hurricane Research Division on Virginia Key.

“But people need to realize that we are still in the active era. Within a year or two, we can expect things to bounce back up.”

“The break”: We had a slightly below average season, thanks to some unanticipated shifts in global weather patterns. Nine named storms formed this year, five of them grew into hurricanes and no hurricanes struck the United States.

The potential “bounce back”: A return to the above-average activity we experienced in 2004 when 15 named storms developed into nine hurricanes, four of which slammed Florida.

Or, even worse, a repeat of the hyperactivity of the record-smashing 2005 season, when 27 named storms became 15 hurricanes, four of them also hitting Florida.

“People should use this break to examine their preparedness and harden their defenses,” Goldenberg said. “They should not be thinking, “Oh good, we’re done with this.”‘

Goldenberg is more than just a hurricane scientist.

He and his family nearly died when Hurricane Andrew leveled much of south Miami-Dade County in 1992, so he has first-hand knowledge of the terror and destruction that a hurricane can deliver.

More to the point, Goldenberg and colleague Chris Landsea led a team that published a seminal study in 2001 documenting the start of a two- to three-decade period of heightened hurricane activity.

That period began in 1995, Goldenberg said. One relatively harmless season likely represents nothing more than normal year-to-year variation within the larger trend, he and others said.

“It’s not going to last,” Max Mayfield, director of the National Hurricane Center, said of the dip in hurricane activity.


A brief, potentially misleading reprieve has happened before.

For instance, a mild season in 1997 – seven named storms that became three hurricanes – was sandwiched between two much more active years. Thirteen named storms and nine hurricanes developed in 1996; 14 named storms and 10 hurricanes materialized in 1998.

Still, before this six-month season began, virtually every expert predicted another above-average hurricane season – and all of them were wrong.

As the season progressed and the tropics repeatedly refused to cooperate with the predictions, federal meteorologists and private forecasters repeatedly lowered their forecasts – and they still couldn’t get it right.

The reasons? A late-developing El Nino and surprisingly dry atmospheric conditions over the Atlantic basin, which includes the Caribbean Sea and the Gulf of Mexico.

El Ninos occur when water in the eastern Pacific Ocean becomes unusually warm. They produce winds that can reach the Atlantic basin and suppress the development and strength of tropical systems.

Alas, the El Nino is expected to fade by the June 1 beginning of the next hurricane season.

In addition, most of the storms that did form this year were pushed away from the United States and Caribbean islands by friendly atmospheric conditions.

But, again, don’t take too much for granted.

“The multidecadal signals are still there,” Goldenberg said. “You just had some stuff this year that depressed it.”

For one thing, the usual number of tropical waves – the seeds of tropical storms and hurricanes – rolled off Africa into the Atlantic this year, about 60 of them. For another, ocean temperatures were extremely warm, and warm water usually fuels tropical systems.

During August, September and October, the peak of the hurricane season known as the “ASO” to scientists, Atlantic water temperatures were 1.1 degree Fahrenheit higher than normal – a significant elevation.

“It was the second warmest ASO on record,” Goldenberg said, calling it further evidence that global warming is just one of many factors involved in climate change.

William Gray and Phil Klotzbach, the scientists at Colorado State University who issue widely reported seasonal forecasts, tend to agree.

“A variety of factors interact with each other to cause year-to-year and month-to-month hurricane variability,” Klotzbach said in a statement intended to explain why this year’s seasonal forecasts were so off the mark.

“It is impossible to understand how all these processes interact with each other to 100 percent certainty,” he said. “Continued research should help us better understand these complicated atmospheric-oceanic interactions.”


It is important to note, however, a fundamental difference between long-range, theoretical seasonal forecasts of activity and shorter-range, actual forecasts of a real hurricane’s path and intensity.

Seasonal forecasts are issued by research scientists such as Gray and Klotzbach and government scientists based in Camp Springs, Md. Real-time hurricane forecasts are issued by Mayfield’s crew of specialists in South Florida.

Those hurricane forecasters produced another season of reasonably accurate predictions, though they missed widely on their intensity forecast of Tropical Storm Ernesto, which unexpectedly fizzled as it reached South Florida in August.

“The last time I checked, the operational forecasts were really good – as good or better than our long-term averages,” Mayfield said.

He plans to retire Jan. 3 and, as his tenure at the hurricane center comes to an end, Mayfield offered this advice to anyone tempted to become complacent:

“If you’re lucky enough to live in beautiful South Florida, you simply must understand that you’re vulnerable to hurricanes. You have to have a plan – before the next season arrives.”

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(c) 2006, The Miami Herald.

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Distributed by McClatchy-Tribune Information Services.

AP-NY-11-26-06 1747EST