All day, from before I got up until after I pulled over for the night.
I'd gone through this before so I had tried to be prepared. All my rain clothes were there in the tent, ready to wear in the morning so I wouldn't have to sit the day out in my tent any more. But there were still some things I lacked.
The journey was miserable without boots. As I drifted along, I saw a bridge over the river and decided to stop there to put on more layers of clothing. It was dry under there, so I could put on another jacket, a pair of gloves, and socks on my otherwise bare feet. Socks alone may not do much when you are sitting in a boat that is slowly filling with water, but the wet material is somewhat better than nothing at all.
As I changed two fishermen appeared, one on either side of the bridge. I struck up a brief conversation and continued on. If the rain really brings up more fish, I didn't notice, but sometimes I think sportsmen just love the misery as much as anything else.
I did notice that they were wearing boots.
Dark and light patches shifted about on the water as I floated on - some chemical or organism makes different areas of the water reflect differently in the rain. I studied these for quite a while, ascertaining that they really did move with the current, and were not mere reflections of objects on shore.
At the end of the day, a few "raindrops" drifted down slowly and erratically. If I wasn't ready for rain, I was surely not ready for the cold stuff.
Day 72 ended: 49*53.479N, 100*22.666W