General manager Dale Tallon announced Tuesday that Weiss will undergo wrist surgery sometime early next week and would be sidelined about three months.
Weiss, the Panthers' first-round draft pick in 2001 and a four-time 20-goal scorer, has endured a difficult season that involved a recent benching and the death of his grandmother. In 17 games, he had one goal and four points, and a minus-13 rating.
"He couldn't perform up to his capabilities, in his opinion, and he wanted to get it fixed," Tallon said. "It was difficult for him and for all of us. Stephen cares and he feels badly about it, but he's got to do what's best for him too. This is a big year for him as well."
"If he's not able to shoot on the power play, it renders him ineffective. We saw a different player in the past and it obviously affected his game. It's a loss for us." -- Panthers coach Kevin Dineen on Stephen Weiss
Weiss, the longest-tenured member of the Panthers, is scheduled to become an unrestricted free agent this summer.
Tallon said he would deal with Weiss' contract situation down the line.
"We'll go into that later," Tallon said. "Let's get him healthy first."
Weiss joins a long list of Panthers regulars on the sidelines.
Goalie Jose Theodore (groin) and defenseman Mike Weaver (lower body) both will be out at least a month; defenseman Dmitry Kulikov will be out 3-4 weeks with an upper-body injury; and forward Scottie Upshall (lower body) and defenseman Ed Jovanovski (lower body) both will be out another seven to 10 days.
Right wing Kris Versteeg will miss his 11th consecutive game Tuesday night against the Winnipeg Jets because of an upper-body injury, but Tallon said he was hoping Versteeg could return Friday night when the same two teams meet again at BB&T Center.
Tallon didn't provide details about whether Weiss aggravated an old injury or when he was injured.
The wrist injury undoubtedly contributed to Weiss being credited with only 19 shots in 17 games.
"If he's not able to shoot on the power play, it renders him ineffective," Panthers coach Kevin Dineen said. "We saw a different player in the past and it obviously affected his game. It's a loss for us."
Weiss had missed four games early in the season with a lower-body injury.
He led the team in scoring three consecutive seasons before finishing second to Tomas Fleischmann in 2011-12 when the Panthers won the Southeast Division and Weiss reached the Stanley Cup Playoffs for the first time in his career.
"It's difficult," defenseman Erik Gudbranson said. "He's really a center point of this team, so it's going to be tough not having him around as much. We wish him all the best with the surgery. Hope it goes well and hopefully he can get back in the lineup or healthy as soon as possible. We're just going to have to make do and find ways to replace him and play stronger as a team."