This is how fast it happens. January 23, it’s frigid, lethal, beautiful open water, slapping happily at shore & ducks. There’s a cold snap (minus 26 at the coldest).
In five days of cold, open water changes to solid crust. There are now ice-fishing huts where there were waves.
Moral of the story: if you’re wondering whether it’s safe to go out there – ask an ice-fisherman from Owen Sound.