I’ve hiked down to Phantom Ranch in July and it was an experience. The rocks are too hot to sit on. The ground is too hot to stand. The river is too cold to wade into for any length of time. It was 125 at the campsite. When the sun went down, the rocks just irradiated heat. I was never more glad to leave than waking up at 1am to hike out. We had to carry the pack of one of our comrades.