21 Jul Prouty Glacier, S. Sister Trip Report
Over the July 12 weekend, Bruce Lakin joined me for a climb of South Sister’s Prouty Glacier route. We were a little surprised at the start of the trip by how crowded the Green Lakes trailhead was when we arrived. The recent warm temperatures must have convinced the hiking crowd that the walk into the lakes would be largely snow free. And, mostly, it was. There were a number of overnighters camping at the lake when we got there but we were able to find a scenic campsite at the north end of the lakes.
That first afternoon we scouted the approach to the glacier. Barely 500 yards from camp we moved onto snow and we continued across connected snow fields to the top of the ridge flanking the south side of the Prouty. It was nice to find this much snow remaining; it would speed up our approach in the morning.
The night was warm and when we started out at 5 AM the snow conditions were soft. More troubling, there were thickening clouds across a red sky. The forecast predicted showers in the afternoon, but it was becoming apparent that we’d see thunderstorm activity earlier than that. We kept a steady pace and soon we were crossing the level main portion of the glacier. Although some indentations hinted at crevasses below, there were few open. Toward the top of the Prouty, a tongue of snow extends up to the summit crater rim. A wide bergschrund was open there and another fracture split the snow ramp a few hundred feet higher.
We traveled up the middle of the glacier, well clear of rocks that had fallen from surrounding cliffs and headed for the lower ‘schrund. Just as we came up on its left edge we herd peals of thunder. We stopped and watched a dark cloud that was quickly moving toward North Sister. 6:45 in the morning and thunderstorms already! We wondered whether to turn around. Bruce took out his smart phone and checked the current radar map. We could see the one cell that was near us and others to the west. But there was a large gap to the southwest before the next storm. We decided that we’d make a try for the top.
I traversed right back onto the snow and crossed the bergschrund in its middle, where a thick bridge remained. The angle steepened and we shifted from a zigzag ascent to front pointing up to the higher ‘schrund. This one extended completely across the snow tongue. I moved up onto the rock on its right side. It was loose and wet, but there were plenty of horizontal features and even with crampons on, we scrambled up easily. Another short steeper section, a few moves across a rock band, and soon we were up on the crater rim.
We could see that the storm to our south was approaching but we guessed its speed meant that we could top out and descend before it reached the mountain. Bruce led across the crater bowl and we arrived at the summit at about 9:30 AM. The view from the top is a delight but we didn’t dare linger. A couple of quick photos and we headed down under darkening skies. Our descent followed the hiker’s trail as far as the Lewis Glacier, and then eastward, through the snow bowls lining the drainage back to the Green Lakes basin. Thunder and lightning chased us to camp, but our luck held and we made the cover of the tent before the rain pounded down. Vindication for an alpine early start.