This walk will take place at the east end of the Grand Canyon, at a side canyon, actually, on the Navajo Reservation.
I happen to live at the other end of the Grand Canyon, near Grand Canyon West. I can't speak for the east end, but where I am, it's extremely windy with some huge gusts. There is no possible way he could attempt this walk at Grand Canyon West. I hope for his sake that the Navajo Reservation end of the canyon is not nearly as windy.
they said they measured 42 mph thermals at mid wire a bit ago.