CHICAGO (STMW) – Sunny skies and mild temperatures could draw people to Lake Michigan beaches this weekend, but authorities are warning swimmers of strong rip currents expected to develop Saturday morning.

The National Weather Service is warning of a rip current risk from 7 a.m. Saturday through Sunday evening for Lake and Cook counties in Illinois and Lake and Porter counties in Indiana, according to the weather service’s website.

Rip currents are powerful channels of water flowing quickly away from shore, the weather service said. They most often happen at low spots or breaks in the sandbar or in the area of groins, jetties and piers.

Strong winds and high waves are expected to develop Saturday morning and produce a moderate risk for rip currents in Illinois and a high risk of rip currents along the Indiana shore, the weather service said.

Swimmers should heed the advice of lifeguards and the beach patrol, the weather service said. Pay attention to flags and posted signs.

People who become caught in a rip current should not panic, the weather service said. Swim parallel to shore until away from the force of the rip current, then swim back to the beach. Do not attempt to swim directly against the rip current because even a strong swimmer can become exhausted quickly.

The weather service is predicting a sunny weekend, with a high of 80 degrees Saturday and 76 degrees Sunday.

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