Garrett Quedens' parents searched the neighborhood after he did not return home from a New Year's Eve party.
A newspaper deliveryman found the teen lying on the side of Watson Avenue around 3:45 a.m.
Police said there was no evidence of foul play or trauma. It was unclear if the frigid temperatures played a factor in his death.
However, an autopsy showed a significant amount of alcohol in his system, police said, but further tests were being done.
Garrett had been hanging out in a wooded area with a friend during the evening Wednesday despite frigid temperatures, said Lt. Jack Fitzpatrick, commander of the Suffolk County homicide squad.
The boys asked 19-year-old Ishmoile Mohammed to buy them alcohol and paid him $10 and extra for gas, Fitzpatrick said. Mohammed then asked a 23-year-old friend, Reynold Jennings, who purchased the vodka, police said.
Garrett and his 14-year-old friend drank, but the friend made it home.
Police have arrested two men. Ishmoile Mohammed III, 19, of 230 Midwood Road has been charged with Unlawfully Dealing with a Child for allegedly providing a bottle of vodka that was consumed by Quedens and a 14-year-old friend.
Mohammed's roommate, Reynold Jennings, 23, was also charged with Unlawfully Dealing with a for providing the vodka to Mohammed.
Both men posted bail and were released.
Authorities said at a news conference on Thursday that Quedens had gone to a party at 8:30 p.m. with friends. His parents had extended his normal 11:00 p.m. to midnight because it was New Year's.
When he didn't return on time, his parents tried to call him and his friends, and began searching for him. They did not report him missing, police said.
Rescue crews were called to the scene after the boy was found. Quesden was taken to Good Samaritan Hospital Medical Center in West Islip where he was pronounced dead.