It stood on Atlantic Walk in the area known as the Wedge, implying its tapered shape, where houses practically overlap. Streets do not exist in the Wedge, only sidewalks and sand alleys for sanitation trucks and emergency vehicles. Those who live there leave their cars in common parking lots and transport their belongings in little wagons.

Long nicknamed the Irish Riviera, even as its population has become more ethnically diverse, Breezy Point is predominantly middle class and working class, home to numerous firefighters and police officers. Houses, some newer ones that stand with a certain hauteur and older ones dating back 70 or 80 years, are often passed down generations. It is a gated community, with its own security force, and residents belong to a cooperative association that owns the land. Originally the neighborhood was a summer retreat, but now its full-time population has swelled to over 60 percent. Not everyone holds flood insurance.

Ms. Serafin, a flight attendant, left Sunday morning to work a flight to Dallas. Phone messages from the cooperative association sputtered in telling Mr. Serafin to evacuate. Like many others, he discounted the storm’s power and moved through the day with a certain insouciance.

At 6:30 p.m., he took a nap. He was jostled awake about 8 p.m. by the sound of rushing water. The basement was flooded. Sockets were hissing. Then he shut off the electricity.

He noticed a glow from a house three doors down on the next street, Ocean Avenue — Gerard Jordan’s summer bungalow, two houses away from the Stehn Promenade and the ocean. Mr. Jordan, 88, a retired food broker, was in a hospital in New Jersey recuperating from heart surgery. His son, Father Brian Jordan, a Roman Catholic priest, had been at the bungalow two days earlier to move deck furniture inside.

In his house just north of the Wedge, an off-duty New York firefighter, Joe Adinolfi, also saw the glow. He tried calling 911 and was peeved that he could not get through. He phoned his Brooklyn firehouse and told them. The Fire Department said it heard of the fire at 8:38.