The 27-year-old rapper, whose real name is Dwayne Carter, pleaded guilty in October to a weapons possession charge and will be sentenced Feb. 9. His plea deal calls for a year in jail.
The charge stemmed from a 2007 traffic stop of his tour bus in New York when authorities said they smelled marijuana, and as they approached, he tossed aside a bag with a loaded .40-caliber handgun.
In a separate case, he also faces trial in March on felony drug possession and weapons charges in Yuma County, Ariz. More recently, he had to postpone a show one day after authorities stopped two of his buses in Texas and found marijuana. The case has been referred to the sheriff's office.
Some of those at Monday's concert said they were disappointed with the rapper's legal troubles.
"It's kinda sad, the stereotype and that he fell into it," said 19-year-old Lee Farrell of New Orleans.
Lil Wayne is set to follow some of rap music's biggest names - from Tupac Shakur, Lil' Kim, Beanie Sigel and Shyne to New Orleans natives Mystikal and C-Murder - who have served a few months to several years behind bars for crimes committed after they became famous.
Corey "C-Murder" Miller was convicted earlier this year of second-degree murder for the 2002 shooting of a fan during a nightclub brawl. He was sentenced to life in prison.
T.I. reported to a federal prison in May for his conviction on weapons charges. He was expected to serve a year and a day, but was released to a halfway house on December 24.
"I hope Lil Wayne will follow in T.I.'s footsteps," said 32-year-old Jed Wright of Metairie, who brought his 11-year-old stepson to the show as a Christmas present. "T.I. promised to turn his life around. Lil Wayne can do the same thing."
Lil Wayne has been rapping since he was a teenager. Over the past two years, his career has reached new heights with several Grammys and gold records. His "Tha Carter III" topped all album sales in 2008 with 2.8 million copies sold. The record had the No. 1 smash "Lollipop."
"He's very unique," said 18-year-old April Nguyen, of Metairie, La. "He expands his genre, even does rock music, and is constantly reinventing himself."
Lil Wayne's next album, "Rebirth" -- which leaked on the Internet on December 16 -- is due for release Feb. 1. After New Orleans, he is scheduled to play a couple of dates in Texas and another show in southern Louisiana.