THOS - ice and avi

*Driving. Tracks were drifting in soon after passing. River crossings had minimal ice shelves but some had icy ramps. There was a report of the big hill needing chains but while traction was iffy, I was able to drive right up. *Approach and the walking on route was ok but unsupportive snow meant it was a bit of a stumble. *Avi hazard on the route was amongst the worst I've seen it. Avalanche Alley had more accumulation than normal although some of the slope had been scoured clean and blown to the valley bottom. Just beyond Avalanche Alley the step of ice that has the small chute feeding onto it was active with a few spindrift avalanches feeding down. *Current conditions would warrant the consideration of Avi gear use. *Throughout Avalanche Alley and through the mid canyon pitches, into the upper canyon, a lot of snow has blown into the canyon and below many steps. It makes for slow passage as trail breaking is extremely tedious. A lot of wallowing and digging is required and previous tracks quickly got filled in. At times it was waist to chest deep sugar and felt soul suckingly bottomless. *As we got into the upper pitches in the canyon the wind got very strong and spindrift was at times constant. Topping out steps meant getting sandblasted by ice crystal like snow. Between the drifting snow and the potential for small avalanches on the walk off we considered rapping instead of the walk off. *Ice conditions on route varied a little bit since snice and shells were common. The sound of running water was often heard. Smaller lower angle steps or top outs often had running surface water under snow and slushy conditions were common. Typically the climbing was easy but some steps had ice that would be tricky to get good screws because of wet snow freezing or slush. Sometimes it was easier just to keep climbing. *We turned around two pitches from the top of the canyon. As we approached the second last pitch which was the lower angled step, the wind and spindrift were relentless, then we witnessed a small avalanche from the gulch to it's left. All the wallowing through deep snow probably made this one of the longest ascents I've had on THOS.

The gully to the left of the second last last ice pitch in the canyon had a wind slab. Fracture line was around the rocky section where it got steeper. The approx 20m slab slid about 10m before stopping. Size around 0.5 to 1. Additionally there were numerous inconsequential spindrift avalanches and one very small slab release from a low angled side slab of rock that was self triggered. There were many instances of cracking as I was breaking trail through deep pockets below ice steps, and wind slabs over deep sugar was common.