With the official start of the Atlantic hurricane season just three weeks away, AccuWeather.com's chief storm forecaster said Tuesday that the East and Gulf coasts should be prepared for as many as five storms with hurricane-force winds.
"I'm very, very concerned about this year," said Joe Bastardi, the private company's chief long-range and hurricane forecaster, echoing the warnings of other meteorologists in recent months.
"The weather patterns that are setting up now on the Atlantic are very similar to those in 1995, 1998 and 2005, and also to some extent 2008," he said. "All these were high-impact years on the U.S. coastline."
The 2005 season produced a record 27 named storms, including Katrina, which flooded New Orleans, and Rita, which struck with Category 3 winds along the Texas-Louisiana border.
An increase in tropical storm activity this season in the Gulf of Mexico could have a major impact on the spreading oil leak there and on efforts to clean it up, said Bastardi. He expects one or two storm threats in that region this season, "if not more."
"It's not going to be like last year," he said. "They're not going to be falling asleep in the gulf this year."
In all, AccuWeather.com is predicting 17 named Atlantic storms this season, with 10 of those reaching hurricane force. Four of the hurricanes would reach "major" (Category 3 or above) status, with top sustained winds of 111 mph or more.
Bastardi believes seven storms will hit the U.S. coast this season, five as hurricanes, two of them "major."
His storm forecast is not much different than one issued in April by the forecast team at Colorado State University. It predicted 15 named storms in 2010, including eight hurricanes, four of them "major."
The National Oceanic and Atmospheric Administration will issue its official 2010 forecast later this month.
The Atlantic hurricane season opens officially on June 1 and continues through November. Storm forecasters have been issuing pre-season predictions since December, with everyone anticipating a much busier season this year than last.
The 2009 season produced nine named storms. Of those, just three reached hurricane force, although two of those became "major" storms. That's somewhat below the long-term average of 9.6 named storms, 5.9 hurricanes. 2.3 of them "major."
Much of the credit for last year's relative quiet has been given to the El Nino conditions that arose in the tropical Pacific Ocean as the 2009 season unfolded.
El Ninos bring above-normal sea surface temperatures to the eastern and central tropical Pacific. That alters weather patterns across broad stretches of the Pacific, the Americas and beyond.
Among other things, meteorologists credit last year's El Nino with changes in the flow of storm systems across the United States that contributed to the record snowfall in the Mid-Atlantic states.
Another effect of El Nino is the suppression of tropical storm and hurricane formation in the Atlantic.
Bastardi said the El Nino event has now "collapsed," and he expects it will be replaced by a La Nina event, which means below-normal sea surface temperatures in the tropical Pacific and a more active Atlantic storm season.
La Nina does not act alone, he said. Among the other factors encouraging more hurricane formation is the "Atlantic Multi-Decadal Oscillation," a decades-long cycle of higher sea surface temperatures in the tropical Atlantic, where many tropical systems are born. That cycle entered a warm phase in 1995 that is expected to last 20 or 30 years.
Bastardi believes the prevailing conditions will set up a hurricane "alley" from West Africa to the islands of the northern Caribbean, including earthquake-ravaged Haiti.
From there, he expects storm tracks will vary, with some moving into the Gulf of Mexico, some into Florida, and others up the East Coast.
Although the coastline from Cape Hatteras, N.C., south is most at risk, Bastardi does have long-term concerns about population centers farther north.
"When I look at the cities up and down the Eastern Seaboard, it's [Philadelphia] I'm most worried about," he said. A storm that moves into the Delaware Bay with a 10- to 15-foot storm surge at the same time as rain-fed floodwaters are moving down the Delaware River would mean a "disaster scenario" for the city, he said.
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