MIAMI, Nov. 29 (UPI) -- An active, destructive Atlantic-Caribbean winds up Friday after producing 15 named storms, nine hurricanes and four major hurricanes. And for the second time in two years, no hurricane hit the U.S. mainland.
The historic average is three hurricane landfalls on the United States every five years.
"But I wouldn't say we were lucky," said Jack Beven of the National Hurricane Center in Miami. "Tropical storm Allison did about $5 billion. We've had a lot of hurricanes that caused less than that."
Figures show that the average annual damage from hurricanes and tropical storms is slightly below that at $4.9 million.
Allison hit the Texas Gulf Coast the first week in June and took two weeks to move over land into the Atlantic. Along with the flood damage, it took 47 lives -- 22 in Texas and Louisiana, nine in Florida, nine in North Carolina, six in Pennsylvania and one in Virginia.
Two other tropical storms hit Florida this year. Barry made landfall on the Florida Panhandle Aug. 6, causing flooding and downed power lines. Gabrielle sloshed ashore between Venice and Saraspta Sept. 14, causing flooding and left a half-million people without power.
On the international front, Iris hit southern Belize with 145 mph winds in early October, taking 31 lives, most of them aboard a Miami-based dive boat that was moored inland.
MIchelle drenched Central America, killing as many as a dozen people, then savaging Cuba and scaring residents of the Florida Keys and urban south Florida as it skirted just to the south of the mainland.
Beven summed up the season as producing "above normal activity, below normal in terms of hurricane landfalls in the United States and like a lot of hurricane seasons, it was fairly destructive."
There were five more named storms than the average of 9.3, three more hurricanes than the average of 6.3, and nearly two more major hurricanes than the average of 2.2.
Beven said some forecasters, including long-range specialist William Gray of Colorado State University, had predicted an active year at least partly because of the absence of El Nino, a warm-weather phenomenon off the coast of Chile that has an impact on the jet stream over North America.
"Some other things we don't know yet. We don't know why there were so many hurricanes at higher (northern) latitudes like Noel and Olga late in the season," Beven said.
Tropical storm Olga, a one-time hurricane, was still loitering in the Atlantic with 70 mph winds Thursday. At 10 a.m. EST, Olga was located near latitude 28.1 north, longitude 60.7 west or about 380 miles southeast of Bermuda and moving southwest near 17 mph. It was expected to continue to weaken over the next few days and may remain a tropical system after the season ends at midnight Friday night.
"The hurricane season may be officially over then, but we'll remain in an unofficial hurricane season mode if that happens," Beven said.
Gray had forecast 12 named storms, seven hurricanes and three major hurricanes. He also predicted an above average a year for U.S. hurricane landfalls, which did not materialize.
Forecasters at the hurricane center attributed the lack of landfalls in the United States to a persistent trough of low pressure along the East Coast most of the season with counter-clockwise winds keeping the storms away.
Spokesman Frank Lepore said steering currents also remained well south of the U.S. mainland.
He said that with all of the storm activity, it was also a science-rich season. He said NASA and NOAA had an array of aircraft that flew into storms at various levels from the bottom to 70,000.
He said that produced a great deal of data that will undergo analysis in the months ahead.
Forecasters also, for the first time, produced five-day forecasts. The maximum in the past has been three days.
Lepore said the forecasts won't be made available to the public until forecasters have more time to refine them.
"They want to try it over a year or two. Uncertainty increases the further out in time you go," he said. "For 72 hours the error is 200 miles. For five days, it might be 400 miles or so."
He said, however, that a new version of the Aviation computer model -- one of several models used in hurricane forecasting -- had cut the error factor by about half.
"They've been tweaking it. This is the first year the improved version of the model was used. It falls under the general heading of evolution," Lepore said. "It certainly got people's attention. It's something you'd want to watch in the future regarding its accuracy over a longer period of time."
