More than 250,000 New Yorkers in low-lying areas have been ordered to evacuate their homes ahead of Hurricane Irene.
The hurricane is expected to blast through New York on Saturday evening (local time).
NY's mayor Michael Bloomberg said the situation was dire. "You only have to look at the weather maps to understand just how big this storm is, and how unique it is. And it's heading basically directly for us," he said.
"This is very serious. Do not be fooled by the sun outside. You just can't wait until gale force winds and driving winds begin."
The city's entire public transport system – which carries 8.5 million people each day – will shut down. Services will stop at noon on Saturday.
All weekend Broadway shows have been cancelled, the Bronx Zoo has closed, and sporting games have been postponed.
According to overseas reports, residents in low-lying areas including the Financial District, have already been ordered to evacuate their homes. This includes residents from Battery Park in downtown Manhattan, the Rockaways in Queens, Coney Island, Manhattan Beach in Brooklyn, and many areas along the shores of Staten Island. Evacuations from coastal areas are believed to be currently underway.
"We've never done a mandatory evacuation before now and we wouldn't be doing it if we didn't think this storm is going to be serious," Bloomberg said.
New Yorkers remaining in the city have been advised to stay inside from 9 p.m. Saturday to 9 p.m. Sunday.
"Stay inside on Sunday. It's a good time to catch up or sleep late," Bloomberg he said.
"We can joke about this on Monday morning, but until then it's a matter of life and death."
Hurricane Irene has already forced evacuations along coastal areas of New Jersey, Maryland and North Carolina.
GALLERY: New Yorker prepare to evacuate from the city
Photo: Getty/ Getty Images Entertainment/ Mario Tama
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