Forecaster Observation - Noisy/Jewel Basin, Swan Range

We headed into Noisy/Jewel Basin on Thursday. Our objective to assess the reactivity of the recent storm snow. On our ascent we noticed localized cracking in the surface snow as we traveled over steep terrain features like small convexities and above tree wells. We observed a recent (previous 48 hours) skier triggered avalanche at the top of Crown Bowl at the head of Noisy Basin (avalanche observation). We also noted widespread, new, large (3-4mm) surface hoar crystals growing on the snow surface.  We dug a snow pit on an east aspect at 7050 feet stability testing at this location confirmed lingering instability on a previously wind-loaded slope. In this area the Feb. 10th rain crust was 80 cm from the surface. The most recent snow was 20 cm deep and this layer fractured and propagated with easy force in Extended Column Tests (ECTP 10). Just below this layer was a soft wind slab on top of lower density snow that also fractured and propagated with moderate force (ECTP 15) (Photo).  The light to moderate winds from early in the week were not able to transport this new snow very far. We dug another pit on the same aspect and moved about 50 vertical feet down the slope. Using the Feb. 10th crust as a reference, we found it 58 cm from the surface in this location. The layers of concern from our previous snow pit were only 10 cm thick and fractured but did not propagate in ECTs.