As Irene surged toward Long Island, Matthew Dower loaded his family and three cats into his car because he knew what he was in for.
"I lived in Florida years ago and made the mistake of not leaving, and that was an ordeal," Dower said Saturday at his home in Massapequa.
Dower was among the more than 400,000 Long Islanders who, in a move of unprecedented proportions, left houses, hospitals and nursing homes in scores of towns and villages as they heeded orders to seek shelter from the approaching storm.
Officials in Nassau and Suffolk issued alerts, activated automated phone systems and in some cases pulled out loudspeakers to encourage people to leave areas in jeopardy of flooding before Irene hit the Island.
For those who failed to listen, they had a stern message: If you don't leave, you're on your own.
To those reluctant to leave, he said: "If you don't care about your own public safety, think about the first responders."
Suffolk County Executive Steve Levy urged people to get out early, because once the wind picked up, he said, "There's no one coming to your home."
Islip Supervisor Phil Nolan said the evacuations were necessary. "This storm really could bring all the problem areas together -- big power outages, trees down and large amounts of water," he said. "We're ready, preparations have gone well, but the magnitude of this storm is such we're in for a severe weather event."
Thousands had left Fire Island following a Friday evacuation order, but others were riding out the storm. "We're not happy about that," Nolan said.
The exodus left some villages eerily empty. Almost all the stores on Main Street in Westhampton Beach Village were boarded up. Someone wrote, "Be Kind Irene" across the plywood on Mustique clothing store, but across the street, it was, "Shock You Irene" in orange letters.
Bayville Mayor Doug Watson said the village was using loudspeakers to get residents to pay attention to an evacuation order.
On Fourth Street, which is notorious for flooding even in heavy rains, some scrambled to leave hours before the storm.
"We've been here for nor'easters, and in '92, we were taken out in a rowboat by the National Guard," Christine Oddo said. "We're not taking any chances; it's not worth it."
Still, some refused to budge.
Town of Oyster Bay Public Safety director Justin McCaffrey estimated that fewer than 50 percent of town residents who fall under Nassau's evacuation order had left their homes.
"Is everything empty? I don't think so," he said. "What you have the most of is: the wife and kids are leaving; the husband is staying behind to make sure everything stays safe."
By midmorning, coastal areas such as Long Beach were bracing for the worst. Stores along Park Avenue were boarded up. A Starbucks near City Hall had sandbags against its locked doors.
At Long Beach Surf Shop on Park Avenue, though, employees said a few customers called to see if they could rent a board.
That prompted a handwritten sign, tacked on the front door: "No Rentals Today. Don't Even Ask."