I'd say a bench like that could easily get to 140 in August. But I live in Texas, and I have a black car with a black steering wheel. I throw a white cloth over it when I park outside in summer, because I literally cannot hold the steering wheel otherwise.
I do not question that sitting on the bench could cause burns, but it is utterly mind-boggling to me that a person could not only to sit there long enough for that to actually happen, but to be unaware of it.
Additionally, there were presumably other people there waiting. Anybody else on the benches? When they jumped up shrieking, was that not enough warning? Did everybody else simply know better than to sit, and that, too, was not enough of a warning for the lone woman on the hot bench?
I am sincerely sympathetic. Burns are horrible injuries and I don't wish that on anybody. But who does not know that black surfaces are hot?
For sure. We had a 100F day here in Indiana, the surface temp on my deck (medium brown stain) was 147F.
And the sun is hotter down there.