Lemhi

The faceted grains buried on Cinco de Mayo (a semi-rare May weak layer!) are the source of the primary slab avalanche concern. This layer produced a significant amount of avalanche activity in wind loaded terrain in the lemhi during loading on 5/5 and into 5/6. Based on weather and other snowpack observations, similar activity likely occurred in the greater region. Observed slab avalanches (1-2' thick) failed naturally in wind loaded terrain and ran quickly downslope on top of the prominent 4/26 crust, entraining plenty of debris. Winds shifted on 5/6 and have been blowing at loading speeds out of the W/NW-ish, continuing to build and stiffen the slabs overlying the cinqo weak layer. Rain lines in the lemhi were high initially (9-9.5k), and lowered to valley floor by 5/6. The presence of the 5/5 layer has me taking a step back from the very steep, big, wide open terrain that I've been comfortably playing in recently. I think the distribution of this layer is probably spotty, but my confidence is low. I expect the slabs over this weak layer will take more time to bond than is typical in May. Ongoing precip and wind loading is not helping this process. It would not be surprising to see triggered slabs failing higher on the slope than the location of triggering, and breaking widely. Looking ahead, expecting to see temperatures warming drastically later in the week. Anticipating a widespread shedding of the snow on top of the 4/26 crust. Initial shed should be confined to this more recent snow, but slides may pick up a lot of speed and debris as the run down and fan out on the 4/26 crust. Lots of good skiing to be done, but it's worth taking the time to plug the brain in and assess and reassess conditions frequently. Lots of variability with changes in aspect and elevation.

Quick report