I started from Grand Mountet Hut at 5h15.
The big crevasses of the Mountet glacier must be crossed by the left. Higher, the traverse of the rimaye is the key of the climb. After the hot days of July, the upper lip of the rimaye is a vertical ice wall of 5 meters, now quoted PD +. This wall is prolonged by a stiff 30 meters long slope of 50° which softens upwards.
I reached the summit at 8 h 15.
We start with some dark weather, durring the climb it became better but halfway the ridge we returned because the weather was changing again an it turned bad. So no Trifthorn summit...
From the Rothorn Hut via the missing snow couloir! to a fine ridge from the Triftjoch to the Summit. Same ridge for descent. Very fine views of the surrounding peaks. Seems a good first day out when out from Scotland.
Snow plod up, lots of lose rock on descent, not too bad for a traverse.