Gov. Andrew M. Cuomo declared a state of emergency Thursday afternoon as the projected path of Hurricane Irene shifted to the west and put it, if projections hold, on a collision course with western Long Island.
The Metropolitan Transportation Authority said that there may be "a partial or full shutdown" because of Irene.
Dickman cautioned that there is a 100-mile margin of error on the storm track, which means the center of the storm could miss Long Island entirely, but the Island would still see high winds and heavy rain in that case.
The governor said Thursday that the state Office of Emergency Management has deployed command vehicles to Nassau and Suffolk counties. The office will make additional deployments of personnel and resources as needed; it is also coordinating with emergency teams across the state to activate local emergency plans.
The state Parks Department has canceled all Friday, Saturday, and Sunday camping reservations at all state parks in the Long Island, Palisades and Taconic regions. A complete evacuation of anyone remaining in the campgrounds will occur at noon Saturday.
The Thruway Authority and Bridge Authority is monitoring conditions and readying trucks to deploy for debris clearing. Meanwhile, the Tappan Zee Bridge will be closed to truck, trailer, and mobile home traffic if winds reach 45 mph, and this traffic will be diverted to other outlets, the governor said.
Cuomo's declaration gives the state numerous options as governments along the coast prepare for Irene's onslaught.
"In this emergency I am activating all levels of state government to prepare for any situation that may be caused by Hurricane Irene," Cuomo said in a news release. "We are communicating with our federal and local partners to track the storm and to plan a coordinated response, and we will deploy resources as needed to the areas expected to be hit the hardest.
"I urge New Yorkers to personally prepare for hurricane conditions and to cooperate with emergency officials if needed," Cuomo added. "By working together, we will all be able to face this storm in a calm and organized manner."
When it gets here Sunday afternoon or evening, Irene is projected to have weakened to anywhere from a tropical storm to a weak Category 2 hurricane, but is still likely to down trees and flood coastal areas, Dickman said.
MTA officials issued a statement Thursday warning riders that some or all services could be shut down during the height of the storm and afterward.
"Because of the severity of the wind and rain associated with a hurricane, there may be partial or full shutdown of our services to ensure the safety of our customers and employees," a transit system spokesman said in a prepared statement. "We are also prepared to implement evacuation plans if the Mayor and Governor decide that is necessary. We urge our customers to check mta.info frequently and to consider the impacts of this storm when making travel plans through the weekend."
Irene will arrive at a period of unusually high and low tides and will bring conditions similar to a very strong nor'easter. High northeast winds combined with the possibility of the storm hitting at high tide could mean trouble for low-lying areas along the North Shore, such as Asharoken and Bayville, and the shorelines of Peconic Bay in Orient and Montauk.
Dickman said the weather service expects about 6 inches of rain. The combination of soggy ground and high winds could bring down many trees and lead to extensive and prolonged power outages, especially on the North Shore, he said.
Shoreline erosion and rip currents along the South Shore are also expected before the storm arrives. The weather service issued a rip current warning for Atlantic beaches Thursday.
A hurricane watch for Long Island could be posted Thursday night, Dickman said.
The National Hurricane Center said in an advisory at 5 a.m. that a hurricane-hunter aircraft found wind speeds of about 114 mph, making Irene a Category 3.
Officials believe the storm will regain intensity over the next 48 hours, then begin to weaken again. However, the Hurricane Center said the storm is so large, it will weaken slowly, and how it continues to develop will depend on whether it stays offshore or hooks over land.
"Since Irene has such a large and intense circulation, it will probably be rather slow to weaken," the Hurricane Center statement said. "Given the limitations in our ability to predict intensity change, there is significant uncertainty as to just how strong Irene will be when it nears the eastern and northeastern U.S. coast."
Irene's core was forecast to continue moving over the northwestern Bahamas on Thursday before heading north toward the U.S. coast, with its current path possibly bringing it to North Carolina's Outer Banks by Saturday afternoon, The Associated Press reported.
As of 8 a.m., the Category 3 hurricane was centered about 65 miles east-northeast of the Bahamian capital, Nassau, the AP said. Forecasters said the winds will ramp up quickly and Irene was expected to blow into a monstrous Category 4 with winds of at least 131 mph, the AP said.
Thursday was to be mostly cloudy with a high near 82, the weather service said. There is a chance of showers and thunderstorms, some with heavy rain, mainly after 3 p.m.
Friday will be mostly sunny with a high near 84. Saturday will be mostly cloudy with a high near 79. There's a chance of showers and thunderstorms, then showers likely and a thunderstorm possible after 3 p.m.
With Yancey Roy