Suffolk County Executive Steve Levy said residents should be prepared to get out upon sudden evacuation orders.

“We have to plan for the real deal here,” Levy said. “Start making your plans now so you have adequate time to deal with the situation.”

Officials say if the storm track does not change, Nassau County will evacuate its barrier islands.

“Be prepared to leave your home on short notice,” said Edward Mangano, Nassau County executive.

Islip Town Supervisor Phil Nolan is already encouraging residents of Fire Island to evacuate.

LIPA has called in extra workers from utilities in Pennsylvania to deal with possible power outages, and Mangano said the county is preparing public shelters at Nassau Community College, SUNY Farmingdale and Locust Valley High School.

Some 400,000 people live south of Sunrise Highway in Nassau County, which could be in the danger zone.

Forecasters say when tropical systems get into northern latitudes, they tend to accelerate faster than the models project, meaning the storm might be out quicker, but not necessarily with a weaker impact.

Even if the storm does not make landfall, concerns include flooding from the tropical downpours, wind damage and beach erosion.

For Nassau evacuation routes and other emergency planning tools, go here. For Suffolk, start here.