Follow the Sabrina basin trail from the dam at Lake Sabrina (9,128') and follow it to Blue Lake. At Blue Lake, keep heading south towards Baboon Lakes. The trail can be difficult to follow through here, and kind of disappears 400 feet below Baboon Lakes. Just keep aiming up to the obvious bench that holds the lakes. Skirt the Baboon Lakes on the east side and follow the inlet stream up towards Sunset Lake. If you are camping, Baboon and Sunset Lakes are nice spots. If you are not camping at Sunset Lake, then do not follow the stream up to the lake. Instead, follow the right hand fork of this stream when it branches just above Baboon Lakes and follow it up to the saddle NW of Sunset Lake (between Peak 12,486' and unnamed point 11,680'+).
Contour above the NW shore of Sunset Lake and aim for the snowfield on the other side of the lake. The route should be obvious from here up to the Thompson Glacier. Once at the moraine, you will see Thompson on the left and Point Powell on the right. The NE Couloir of Powell will be the incredibly obvious chute right in front of you.
The route is as straightforward as it gets: Don your crampons, get in the chute, and start climbing. At the top, turn right and walk up 200 vertical feet to the summit block. Congratulations. Enjoy the view.
The chute averages about 42 degrees (38-ish at the bottom, 45-ish at the top). In late spring/early summer, the top 1/3 of the coulior may be melted out, revealing loose rock underneath. This is tedious to climb, and can be dangerous with a larger party as rockfall is a serious hazard.
The couloir would make for an incredible ski descent in mid-spring (after the road opens up to Sabrina, but before the snow melts out too much)
Ice axe, crampons. A helmet would have been nice to have for the rockfall hazard.
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