I was at a protest last winter in Chicago. I believe it was 16 degrees. It was insane. My buddy and I bundled up. Layers. He brought heat packs. We prepared.
It was still brutal. We found walking helped but damn. I think we only lasted just shy of 2 hours. We tried but even my thick thighs (covered by my thick fur lined parka coat) were starting to feel pain from the cold within the first hour.
I say this because that's still 25 degrees warmer than it was for these people
Damn that's some hardcore protesting in Minnesota.