CHICAGO (WLS) -- Dangerous swimming conditions and minor flooding are expected Saturday along southern Lake Michigan, according to the National Weather Service.
Dangerous swimming conditions because of strong rip and structural currents were expected to begin around 1 p.m. along the beaches and shoreline in Cook and Lake Counties, the weather service said in a Beach Hazards Statement.
Rip currents are powerful channels of water that flow away from the shore and can sweep swimmers into deeper water. The warning is in effect until late Saturday, the weather service said.
In addition, winds up to 20 mph could bring waves as tall as 6 feet crashing into the shorelines, the weather service said. The record high Lake Michigan levels will be conducive to minor flooding along the shoreline, likely along the lakefront bike path, the weather service said. The flood advisory is in effect until 4 a.m. Sunday.
Dave Benjamin, with the Great Lakes Surf Rescue Project, explained how lake conditions can change in an instant.
"You're jumping around, playing in waves where an area may seem somewhat safe and a sandbar can break down, a trough can open up the water can start piling up on shore and now you have a new rip current channel," he said.
High waves and rip currents closed down Whihala Beach in Northwest Indiana.
"We came to the beach but there's no beach. It's covered in water," said would-be beachgoer Jose Rodriguez.
Some like Steve Gantz stuck around to watch the action.
"It gets this way every few weeks. It gets exciting to watch. I walk over here and check out the waves," he said.
A lifeguard on the South Side rescued a 27-year-old swimmer who was pulled further out into the lake, officials said.
Another swimmer was not as lucky late Saturday. Authorities said a 17-year-old boy had gone missing in wave conditions near Michigan City. The U.S. Coast Guard deployed a helicopter and a boat to search for him as the waters were too dangerous for divers to enter.
The Chicago Sun-Times Media Wire contributed to this report.
Swimmer missing near Michigan City as weather service warns of life-threatening waves