NEW YORK — Hurricane evacuation areas would encompass 640,000 more New York City residents, and the number of zones would double, in plans unveiled Friday.
Details on the new zones will not be released until June, but the changes could mean neighborhoods across the city might be told to clear out ahead of future storms, even as the city grapples with findings that nearly two-thirds of people shrugged off orders to leave before Hurricane Sandy.
Officials aim to expand the size and the number of zones to tailor evacuation orders to the dynamics of a particular storm, Deputy Mayor Caswell Holloway said.
The idea: ‘‘Only dislocate the people who need to be dislocated and ultimately give people more confidence’’ that evacuation is needed, he said at a briefing on the city’s analysis of its handling of Sandy.
More than 2.3 million people live in the city’s three evacuation zones now. Some 375,000 residents of the most vulnerable area, Zone A, were told to leave a day before Sandy hit New York on Oct. 29.
But a survey of Zone A residents found 63 percent stayed home, the report said.