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Temperatures in Bridgers above freezing

Mar 9. We rode out Lionhead Ridge... there were two or three shallow small wind slabs below Lionhead Ridge. Photo: GNFAC

Mar 9. We rode out Lionhead Ridge... there were two or three shallow small wind slabs below Lionhead Ridge. Photo: GNFAC

We rode out Lionhead Ridge and around the north end to the head of Targhee Creek. Skies started overcast, but cleared through the day as wind calmed from moderate to light out of the west and southwest.

There were zero recent large persistent slab avalanches, and there were two or three shallow small wind slabs below Lionhead Ridge. The snow surface became moist, but crusts from previous warm days and cold night only softened slightly. There was very little, if any, wet snow avalanche hazard today.

We dug at the top of Lionhead Ridge on the south side of Airplane Bowl. 9,300', NE aspect. There was a 2.5' deep very hard slab (1f to P+) above soft facets (4F-), snow depth of 5 feet. We had ECTX, but with extra hits and some removal of the slab it propagated with a clean break. The persistent slab avalanche problem is becoming more stubborn, but not going away. For now it is not likely, but there is probably an isolated slope where you could trigger an avalanche, and we could see this problem arise again with more snow next week.

We skied to Flanders Mountain, traversed the ridgeline, and dropped into the northwest-facing terrain near the Winter Dance Buttress down to the Main Fork. Ridgelines had moderate to strong winds but minimal transport as snow at upper elevations had already moved or had hardened with recent wind and warm temperatures. Wind Slabs that we assessed were stubborn to unreactive, but there is probably one out there that could result in a small avalanche. No signs of dry snow instability during the tour or in our snowpack assessments (Flanders Bowl - ECTN Teens and 20s and Near Winter Dance Buttress - ECTN Teens and 20s). Snow surfaces were warming (wetting) in south-facing terrain and on all aspects below 8000' by 3 PM. However, we did not see any natural wet snow activity. 

I would be watching out for isolated wind slab instability and wet loose avalanches for now. 

Somewhat fresh looking slab avalanche in upper Storm Castle Creek on an East facing slope. Looks like there might be a wet loose slide to the right of it as well. One small wet loose avalanche, probably from yesterday, in Maid of the Mist bowl. 

Widespread wind effect in the alpine of Hyalite yesterday. The windslabs were fairly stubborn however, and were only breaking in very small pockets, not propagating outwards. Where the recent snow was still protected from sun and wind, large dry loose slides were easy to trigger.