Weight will also remain as an assistant coach on Capuano's staff, the Islanders said Monday.
The 51-year-old Cronin spent the past three seasons as an assistant with the Toronto Maple Leafs. Before that, Cronin was the head coach at Northeastern University for six years, where he earned the Bob Kullen Coach of the Year Award in Hockey East in 2008-09.
From 1999-2003, Cronin served as an assistant with the Islanders. His first head coaching position came in 2003 when he led the Islanders' Bridgeport AHL affiliate. In two seasons with the Sound Tigers, he was 78-61-12.
Cronin also was an assistant with the U.S. National Development Program Under-18 team, the University of Maine, and Colorado College. He got his start as an assistant at Colby College.