CHICAGO (AP) — The U.S. Coast Guard has a warning for people along Lake Michigan: While the weather may be unseasonably warm, the water is still dangerously cold.

Mike Baron is a recreational boating safety specialist for the coast guard. He says: “Warm air temperatures can create a false sense of security for boaters.”

Baron says water temperatures in Lake Michigan are hovering around 40 degrees. He also notes that cool water drains body heat as much as 25 faster than cool air, and survival time is diminished greatly when someone is in water that’s below 70 degrees.

Baron says boaters should dress for the water temperature, not the air temperature.

The coast guard also recommends boaters wear a dry suit to increase chances of surviving a fall into the lake.