"The first time we get hit here with a Category 2, it's going to be disastrous," said meteorologist Michael Wyllie of the National Weather Service, referring to the scale used to rate hurricane strength.
Wyllie said powerful storms have missed New York in recent years, unlike parts of the Gulf Coast, where periodic storms "thin out the trees and the buildings."
Gloria, the last big storm to hit the New York area, caused about $900 million in economic losses along the East Coast in 1985, according to the National Oceanic and Atmospheric Administration.
"It's not like we can all run down to Home Depot and pick up these two-by-fours to board up windows," said John Koch, lead forecaster at the NWS forecast office in New York. "What we want people to do is know what they are going to do with their family and their pets."
Koch urged residents to familiarize themselves with the location of evacuation zones and make plans to have extra dry clothes, medicines, batteries, water and copies of valuable documents.
U.Va. researcher says temperature isn't only factor for hurricanes
Global warming by itself cannot be blamed for the increase in severe Atlantic hurricanes, University of Virginia climate researchers report.
"It is too simplistic to only implicate sea-surface temperatures in the dramatic increase in the number of major hurricanes," said the study's lead author, Patrick J. Michaels.
Warm water fuels tropical cyclones. Some hurricane researchers have related warming in the Atlantic basin with greater hurricane severity, pointing to greenhouse-induced atmosphere warming as the cause for the ocean heating.
But hurricanes' ultimate strength is not directly linked to the underlying water temperatures, the Virginia scientists said.
"There are more severe hurricanes appearing than are explainable by the rise in sea-surface temperatures since the 1990s," said Michaels, a professor of environmental sciences and director of the Virginia Climatology Office.
Michaels is a leading skeptic of global warming's potential harm.
To fire off monster hurricanes of Category 3 or stronger, the brewing storm has to move over water with a temperature of at least 83 degrees.
Areas where the water is regularly hotter, such as the Gulf of Mexico and the Caribbean Sea, won't see more intense storms than in the past, Michaels said.
"At that point, other factors take over," he said, "such as the vertical wind profile, and atmospheric temperature and moisture gradients."
The U.Va. climatologists found that increasing water temperatures account for only about half of the increase in strong hurricanes over the past 25 years.
"We should have had 28 Category 3 storms from the warming" between 1995 and 2005, Michaels said. "Instead we had 42." By comparison, 16 such storms developed between 1982 and 1994.
Michaels believes the increase in hurricane activity beginning in the 1990s is related mainly to variation in the North Atlantic's temperature patterns, not temperature change itself.
"The pattern can appear whether it's cool or whether it's warm," he said.
While expanding the 83-degree zone ought to produce more severe hurricanes, Michaels said, that expansion would also place the storms farther north in the Atlantic, "where there are very few things to hit."
"In the future we may expect to see more major hurricanes," Michaels said, "but we don't expect the ones that do form to be any stronger than the ones that we have seen in the past."
The Virginia study looked at the water temperatures along the paths of the 205 Atlantic tropical cyclones since 1982, providing a more precise picture of the tropical environment involved in each hurricane's development.
The study will appear today in the journal Geophysical Research Letters.
Michaels did the report with U.Va. environmental science professor Robert E. Davis and Paul C. Knappenberger, a former graduate student in environmental sciences at Virginia.
