Burrito does not wear sunscreen, much to my dismay.
I didn't either the first year I went in 2008, and returned to Seattle after that weekend with the worst sunburn of my life. I was dark red everywhere on my body that had been exposed to the sun, and I remember peeling for about 3 weeks afterward. Wear some damn sunscreen.
Saturday was probably about the same temperature that the entire weekend was during 2011, but for some reason I had a much, much easier time operating this year. It was the earliest I went in all weekend and I somehow managed to get drunk and stay drunk all day and night without ever having any issues with the heat. I probably should have died. I mean shit, I was in the 1pm Trash Talk circle pit.
That's one nice thing to count on, there's usually a steady breeze at Sasquatch. I remember every day in 2009 being in the upper 80s / low 90s but weather history for the location shows low 80s all weekend. So many people got taken away in ambulances for heat exhaustion. There really aren't many places to hide inside the amphitheater if it's a hot day. Any areas of shade will be full of people until the evening.