It’s 9 A.M. It’s Time To Start Partying And Grab Your Christmas Onesie.

It just so happened that the celebration started at nine in the morning.

With an 82-foot tree in Rockefeller Center, a stunning light show at Saks Fifth Avenue, picture-postcard ice skating in Central Park, and ballet dancers jetéing through “The Nutcracker” at Lincoln Center, New York City traditionally celebrates Christmas in grand style. There are house parties, cocktail parties, and corporate gatherings. And while sober early-morning dance parties are becoming more and more common, very few drunken gatherings call for an alert.

The 9 a.m. Banger, an all-ages dance party with DJs and a few hours of free drinks, has recently become a New York classic despite all odds. It moves across the city, attracting a youthful population that seems to appreciate the novelty of a crazy morning out.