MILWAUKEE COUNTY, Wis. (CBS 58) -- The Milwaukee County Sheriff's Office (MCSO) is asked the public's help to find a missing 55-year-old man. 

Authorities say Charlie Brown has not been heard from since Thursday, Aug. 21. He was last seen on surveillance video just after 11 a.m. Friday, Aug. 22, walking toward his sailboat at McKinley Marina on Lincoln Memorial Drive. 

Officials say Brown was wearing a short-sleeved blue and white checkered flannel shirt, with dark colored shorts, and brown flip flops. 

Brown has a red and white Bristol B32 sailboat (Wisconsin Registration No. WS1746GL) in the McKinley Marina. "Rossa" is painted on the rear of the boat, which has also been missing since Friday, Aug. 22.

If you have any information regarding the whereabouts of Charles Brown, please contact the MCSO at 414-278-4788.