According to an announcement released November 18, by Coast Guard District 9 headquarters in Cleveland, Ohio, on the afternoon of November 17, during a heavy weather exercise in large waves off Oswego Harbor, one of two 47 foot Coast Guard lifeboats rolled more than 90 degrees, resulting in injuries to several crew members.

 At the time of the incident, windspeeds were unofficially measured by observers on the former coal pier at between 50 and 63 MPH. "Our instrument was averaging 45 mph or so, and while they were out, we all saw it hit 63. Add that to the effect of our building, which makes the anemometer read low, and you've got a serious blow," said one source, who witnessed the broach and observed the highest wind speed. 

Asked how he happened to be present on such a day, he said, "It's unusual to see so much air. We're sailors. Sailors are students of the wind. We like to come down when it blows, take it all in, maybe learn a little something."

According to those present, even with lake levels several feet below normal, the waves were topping the cement breakwall in places and totally submerging the east barrier just outside the main harbor.

The Coast Guard frequently takes advantage of extreme conditions to train crew members.

"Visibility was poor due to darkening skies and blowing spume off the breakwalls, but we watched them practice in the harbor, then head out into the lake. Both upper control stations were crowded with crew in orange and blue drysuits. Outside, they handled the seas well while head to wind, often virtually disappearing in the troughs, so we knew there were 15 footers out there. After a few miles of offing, both turned and ran downwind toward the harbor mouth. I was watching when the boat closest to the lighthouse, about a quarter mile out, was practicing holding its position, but they got caught by an oncoming wave."

One watcher said, "It was all so fast...hard to see exactly what happened, but I know from experience that when you broach, its usually because you don't breast the next wave squarely. The boat almost stops and you lose steering. The wave rolls you and the boat goes whichever way it wants. All you can do is hold on and hope you don't get swamped. That must be close to what happened to them, because they broached really hard."

During strong winds, the waves near harbor entrances are often confused, larger, and closer together than out in open water. Broaches of this kind are not unheard of. To see how it happens, check this YouTube video. The report from Cleveland reported the winds at 30 mph, but did not provide further details of the accident. Here is the link to the official report