In May 1996, Weathers was one of eight clients being guided on Mount Everest by Rob Hall of Adventure Consultants. Weathers, who had recently had radial keratotomy surgery, soon discovered that he was blinded by the effects of high altitude and overexposure to ultraviolet radiation, high altitude effects which had not been well documented at the time. On May 10, the day of the summit assault, Hall, after being told Weathers could not see, wanted him to descend to Camp IV immediately. He, however, believed his vision might improve when the sun came out, so Hall had advised him to wait on the Balcony (27,000 ft, on the 29,000 ft Everest) until Hall came back down to descend with him.