Posted on 01 Dec 2011
The 2011 Atlantic hurricane season was a study in contradictions: It spared the usual Southern targets, while Irene paralyzed the Eastern seaboard and devastated parts of the Northeast with deadly flooding.
The season ended Wednesday as the sixth straight year without U.S. landfall of a major hurricane, yet Irene was one of the costliest storms in U.S. history and killed at least 47 people here and at least eight more in the Caribbean and Canada.
Irene was not considered a major hurricane because it did not have winds exceeding 111 mph (178 kph), or Category 3, when it made landfall in North Carolina on Aug. 27.
"You would think the impacts would be somewhat light, but the damages caused by Irene will be up there in one of the top 30 or so storms," National Hurricane Center Director Bill Read said.
The season produced the third-highest number of tropical storms on record, with 19, but only a slightly higher-than-average number of hurricanes, with six.
Read said low pressure systems on the East coast and high pressure systems over the central U.S. created favorable steering currents that kept the storms mostly churning far out to sea.
Storms won't move into high pressure, clearing the way for an easy storm season for the U.S. Gulf Coast. An exception was Tropical Storm Lee, which formed off the Louisiana coast and drenched much of the eastern U.S.
"It was another very odd year," said Dr. Jeff Masters, Weather Underground's director of meteorology.
The rare combination of near-record ocean temperatures but unusually dry, stable air over the Atlantic was partially responsible for the unusually high count of named storms, Masters said.
Hurricane Ophelia was the strongest storm of the season, at one point strengthening to a Category 4 with 140 mph (225 kph) winds when it was just northeast of Bermuda. Ophelia hit southeastern Newfoundland, Canada, as a tropical storm, but caused little damage.
The last major hurricane to hit the U.S. was Wilma, which cut an unusually large swath of damage across Florida in 2005.
Irene caught many New England residents by surprise in late August, following a rare path as it brushed up the Eastern seaboard from North Carolina, across the Mid-Atlantic and near New York City, where meteorologists said they couldn't ever recall a direct hurricane hit.
Broadway shows were cancelled as New York officials ordered 370,000 people to leave their homes in low-lying areas and immobilized the nation's biggest subway system. Yet, the city sustained only high winds and heavy rains as a weakened Tropical Storm Irene churned up the coast.
Tropical Storm Irene was by far the most destructive event to hit Vermont in almost a century. Flooding from the storm, which dumped up to 11 inches (nearly 28 centimeters) of rain in some areas, killed six people, damaged or destroyed hundreds of miles of roads, scores of bridges, hundreds of homes and left hundreds of people homeless.
About a dozen communities were cut off by the storm for days, many without electricity or phone service and they had to be supplied by National Guard helicopters.
Three months after the storm, most of the roads and bridges have received at least temporary repairs, though two bridges remain closed. The final repair estimate for the roads could reach $250 million, which doesn't count damage to private property.
The state of Vermont's office complex in Waterbury was inundated, forcing the relocation of the offices of many of the people who worked there as well as the permanent closing of the State Hospital, forcing mental health officials to farm out patients needing the most intensive care.
More than 7,000 people asked the Federal Emergency Management Agency for assistance.
The severe flooding "was beyond what most people expected up there so we still have work to do on how to convey how serious the inland flooding events are from these tropical storms," Read said.