Beware boaters and swimmers: High winds on Great Lakes this weekend

The National Weather Service has issued a Great Lakes alert for high waves and strong currents,  which present dangers for boaters and swimmers, for west Michigan beaches from midnight Friday through Saturday evening.

The weather service said high waves , strong currents and dangerous swimming conditions will be around until Sunday.

"The south side of piers and breakwaters will be especially dangerous," the alert said. "Piers and breakwaters will likely be over-topped by waves, which will sweep people into the water."

South-to-southwest winds with gusts generally less than 15 knots (17 mph) will increase Saturday ahead of an approaching cold front. Winds Saturday will reach up to 20 knots (25 mph) with gusts up to 25 knots (nearly 30 mph,) especially across Saginaw Bay into the Lake Huron basin. There, conditions may become hazardous for small crafts, the weather service said.

After 4 p.m., west winds will be moving east at 35 mph with gusts up to 65 mph. 

Dave Benjamin, executive director of public relations and project management for the Great Lakes Surf Rescue Project, said looking at the warm weekend, southerly winds can cause offshore wind conditions for southeast Michigan.

"As the winds travel farther north, the winds will also create waves and dangerous currents such as long-shore currents, rip currents and structural currents," Benjamin said. "The south sides (windward sides) of all piers will be the most turbulent and dangerous spots on Lake Michigan."

Water rescue crews continue to search for Brian Herrmann, 38, who went missing Thursday after he, his wife and their two children were swept into Lake Michigan from the mouth of the Big Sable River at Ludington State Park in west Michigan.

Herrmann is the second swimmer to be reported missing this week at the park, which is northwest of Grand Rapids.

Since July 18, a 14-year-old girl and 18-year-old man have died in separate swimming incidents near the park.

► More: Coast Guard rescues 2 men from capsized boat on Lake Huron

Isolated thunderstorms may occur during the dry weather that's expected through the weekend. In Metro Detroit, Saturday will reach a high of 88 and Sunday will reach 89, both days expected to see more than 50% humidity.

On Sunday, winds decrease out of the southwest. Chances for thunderstorms will increase on Monday ahead of a stronger cold front tracking east across Lake Superior.

Pay attention to flags

Beachgoers and others, experts say, are often unaware of the sea-like characteristics of the lakes and how quickly surf conditions can change. Sustained winds and rolling waves, along with structural obstructions, can create dangerous currents, even along the shoreline.

Frequently, swimmers ignore Michigan’s flag-warning system, which lets beachgoers know when it’s safe to swim. A red flag means stay out of the water and remain on the beach.

■Red = STOP. Stay out of the water and on the beach.

■Yellow = CAUTION. Watch for dangerous conditions and high waves.

■Green = LOW. Swim or wade but remain aware of changing water conditions.

Source: Michigan Department of Natural Resources

srahal@detroitnews.com

Twitter: @SarahRahal_