On June 20, as a pair of climbers was ascending the south buttress of Mt. Tupper, wet, snowy conditions slowed their progress in the upper third of the route. The climbers did not bring ice axes and crampons for traversing the final snowy ledges to the west ridge near the top, nor did they carry bivouac gear. The pair realized they were a long ways from the top and that they were unprepared to retreat or continue. They stopped on a sloping, three-meter-wide ledge and called Jasper dispatch for a rescue. A Parks Canada Visitor Safety team responded via helicopter, and both climbers were slung out.
As mountaineering routes dry off at the beginning of the climbing season, one needs to remember there may still be lots of snow lingering on ledges. The previous week had brought much rainfall, so there was a lot of moisture running down the mountain. The quartzite on Mt. Tupper is generally quite solid, but much of it is covered with a thin veneer of lichen that becomes very slippery when wet. Had the climbing party taken more time to scope their intended route, they would have seen dark water streaks in most of the corners, indicating the route was not dry. They also did not bring the appropriate gear to complete the route (ice axe and crampons).