A search for Leonel Dominguez, 31, of New York, was launched Monday afternoon off Beverly Shores, just west of Michigan City, Ind. It will resume in the morning.
Dominguez has been missing since 3 p.m. after the $20 raft he bought Sunday overturned.
"The wind was gusting up to about 35 miles an hour. There were up to three-foot waves with a lot of white water," said Gene Davis, Department of Natural Resources conservation officer.
Officials say Dominguez convinced his friend Evelyn Hernandez to go on the raft with him. Earlier, the two had made it back to shore safely but decided to go back into the water with the raft when winds began to pick up. The raft flipped and blew away. Dominguez apparently went under while Hernandez called for help. A Marine named Nick ran in the water to rescue her.
"She had given up all hope and she knew she was going to drown, so when Nick was able to swim up there, he definitely saved a life," said Davis.
Neither Hernandez nor Dominguez was wearing a life jacket.
Residents in the area know how dangerous Lake Michigan can be even on a nice, sunny day.
"When you hear a siren, no big deal, somebody did something wrong. When you hear a parade of sirens, it is like, okay, who are we looking for? It happens every year," said Frank Hardwick, Beverly Shores resident.
Back in Chicago near Addison Street, rescuers and lifeguards pulled a female swimmer out of the water who was caught in the winds too far off shore.
"The life guard came, tried to help her and the lifeguard was having a hard time so I went in the water and helped," said Joe Prozanski, witness.
It was a challenging day for lifeguards. A Park District lifeguard had to be rescued after winds pushed his row boat too far out, making it impossible for him to row back in.
Officials remind residents always to wear life jackets when on the lake..