When I checked the Nenana Ice Cam yesterday the Tripod was still standing on the ice, but I didn't realize the event was already over.
It seems the ice broke up just enough to allow the Tripod to move a short distance to trip the clock in the tower it is attached to by a long cable.
The hitch was most of the ice was still in the river, and the Tripod evidently flowed upstream only just a little, which is to the right on the screen, and very odd. Normally it flows downstream, obviously.
I should have realized something was up because the flag rope was down, lying on the ice.
When I checked a few hours later the Tripod was gone and the water was flowing and I realized I had missed it as the ice cam page had the message:
THE ICE OFFICIALLY BROKE AND THE CLOCK STOPPED ON APRIL 30TH, 2021 AT 12:50 PM AST. THE 2021 JACKPOT IS $233,591.00
Should have looked for that message the first time.
The Washington Times had the story here.
So add another Ice-Out to the period April 30-May 7 when the vast majority of them have occurred anyway since 1917. The National Weather Service pretty much nailed it predicting April 29-May 5.
Hard to go wrong with that in any year, to be honest.