Updated 08/08/13 – 11:46 a.m.

CHICAGO (CBS) — The National Weather Service is warning people to stay out of Lake Michigan today, because of large waves and dangerous rip currents along the lakefront in Illinois and Indiana.

“Dangerous pounding waves and life-threatening rip currents are expected at the beaches. People visiting the beaches should stay out of the water,” the National Weather Service said in a beach hazard statement this morning.

The warning remains in effect through 9 p.m. Chicago time.

Rip currents don’t pull swimmers under the water, but rather away from shore. Swimmers drown when the panic and try to swim toward shore against the current and become exhausted.

If you get caught in a rip current, stay calm and swim parallel to the shore until you are out of the current and then you can swim toward shore. Rip currents are typically narrow and once you swim to the side, you can escape.

As of 11:45 a.m., swim advisories had been issued at nine Chicago beaches, although several of those advisories were related to water quality. A swim ban also had been issued at Foster Beach, due to hazardous surf, according to the Chicago Park District.

You can check the status of beaches near you by clicking here.