The technical sergeant was serving in Afghanistan with a security forces unit attached to the New York Air National Guard.
Lemm, who lived in West Harrison, is survived by his widow, Christine, and two children, Brooke and Ryan. He was nicknamed "Superman."
The New York Tenors, along with the Clyde McPhatter's Drifters and other artists, are performing to raise money for the family.
The concert is sponsored by the Stephen Siller Tunnel To Towers Foundation. A mission of the foundation is to honor the sacrifice of firefighter Stephen Siller who died during the Sept. 11, 2001, terrorist attacks on New York. They also honor military and first responders who continue to make the supreme sacrifice.
Doors open at 6 p.m.; and the show begins at 8 p.m. The theatre is at 149 Westchester Ave. in Port Chester.
Tickets are $60; $75; $100; $150 and $300. Click here to purchase tickets.
To donate, visit NYPDSuperman.com.
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