Some relief on storm front
Weather experts say there probably will be fewer tropical storms and hurricanes than originally predicted in May.
By TAMARA LUSH
Published August 8, 2006
Just as the 2006 hurricane season approaches its peak, meteorologists at the National Hurricane Center will release some good news today: This year's hurricane season likely won't be as bad as predicted.
The Miami-based center will downgrade its May forecast, when it predicted 16 named storms in the Atlantic, with as many as six major hurricanes.
Today's announcement shows that for all the sophisticated weather forecasting technology available, hurricane prediction remains an imprecise science.
Experts say meteorologists have improved at determining when and where a storm will strike land. But predicting how atmospheric and oceanic changes will affect an entire hurricane season is much more difficult.
"We're very bad at seasonal forecasting," said Jeff Masters, the co-founder and meteorology director of wunderground.com, a weather forecasting Web site. "It's only slightly better than flipping a coin."
The hurricane center's downgrade comes a week after researchers at Colorado State University also predicted fewer storms than they forecast earlier this year.
The researchers, including noted expert William Gray, reduced the number of likely named storms from 17 to 15 and hurricanes from nine to seven. Fifteen named storms would still make 2006 an above average year, though far less active than last year when 28 storms formed.
Why the downshift in forecasts? Experts link it to the ocean and the atmosphere. Both can change dramatically over the course of a summer.
Sharan Majumdar, an assistant professor of meteorology and physical oceanography at the University of Miami, said there are several reasons why a hurricane season can appear menacing in May but less so in August:* SEA TEMPERATURES. "The ocean surface temperatures in the western Atlantic are considerably cooler than they were last year," he said. Warmer water fuels hurricanes.* Vertical wind shear. Trade winds blow from the east and affect the lower levels of a storm. Some years bring strong winds from the opposite, westerly direction. Opposing wind directions break apart storms. That's what happened with the recent Tropical Storm Chris. "It's difficult to say ahead of time if this will be a high wind shear season or a low wind shear season," Majumdar said.* Low pressure systems. This year's air pressure in the Caribbean isn't as low as it was last year but is at a more normal level. Majumdar says scientists don't really know why some years have more low pressure systems than others.
Philip Klotzbach, the lead researcher on the University of Colorado team, said people need to continue to prepare for major storms, even though the forecasts change throughout the season.
"We are trying to give people the best info we have available," said Klotzbach. "As we get closer to the season, we have a better idea how the atmosphere and ocean are functioning."
Tamara Lush can be reached at 727 893-8612 or at firstname.lastname@example.org.