Freaque waves in Lake Michigan

This news in Chicago local Evanston Review yesterday:

Two Evanston residents were pulled from Lake Michigan waters south of 
Dempster Street Tuesday afternoon after their boat was hit by a "rogue 
wave," capsizing the vessel into the water.

Evanston fire rescue personnel teamed with members of the city Parks and
 Recreation department and U.S. Coast Guard, pulling the couple, a 
66-year-old male, and 47-year-old female, to safety, said Evanston Fire
 Chief Alan Berkowsky.

reported a "rogue wave" in Lake Michigan. That itself is newsworthy. Of course my immediate question is "What kind of rogue wave?"

Berkowsky said the victims were pulled from the water about a half mile out.
 He said they were then placed on the Coast Guard boat and then taken to the
 Coast Guard's station in Wilmette Harbor.



Both boaters were evaluated by Wilmette Fire paramedics and then released,
 he said.



Berkowsky described the boaters, who were not identified, as experienced. He said the boaters said their boat was capsized when hit with what they described as a "rogue wave, a large wave which basically took them by surprise and rolled the boat over."

That certainly answered my question. "A large wave took them by surprise" clearly signified the stipulation that a freaque wave was encountered.

So it reminds us again that a freaque wave can happen any place, any time with no advance warning to take us by surprise. But we are still don't have any notion of what, where, when, how or why it occurs!