New snow accumulated yesterday at treeline to nearly 7-8", & in the alpine to almost 12". Mild temperatures below 8500' brought wet & dense snow, whereas above that dry snow prevailed. Winds were strong, out of the Southwest with a gust to 73 mph recorded. The new snow particles were being compressed by the winds & creating a creamy appearance on the surface. The slabs that formed have a lot of mass & will be easy to trigger with the weight of a human.
New accumulations sit atop of an older wind slab. Below that wind slab the metamorphism of snow grains has occurred, known as faceting. This process turns denser & more cohesive layers of snow into a loose & poorly bonded structure. The larger pore spaces & unstable array allow for avalanches to spread further across the slope, propagation.
This situation could persist for some time into the winter, or may never leave our avalanche hazard scheme.
Mild temps below 8500' brought moisture rich snow to this elevation band. As the suns arch across the sky increases solar radiation & temperatures, its progress along different aspects will loosen snow sequentially. Roller balls & wet sluffs correlate to instability.
Time & wind will permit the new snow to gain strength. Previous storms have deposited wind slabs on North through Southeast aspects. The absence of precipitation & above normal temps for periods of our winter have allowed faceting to occur below these wind slabs. Facet layers below the slabs have been the failure point for many of the pit tests & suggest that this be a layer of concern.
Depending upon your elevation wet snow & rain fell below 8500' & cold dry snow above that. Winds scoured & transported snow across the landscape creating slabs on North through East aspects. Today, spotty clouds & warmer temperatures in the morning & afternoon. Tonight another, hopefully more prolonged, system moves into our area bringing snow & mild temps tomorrow.
This snowpack summary applies only to backcountry areas in the Bridgeport Winter Recreation Area. Click here for a map of the area. This snowpack summary describes general avalanche conditions and local variations always occur. This snowpack summary expires in 48 hours unless otherwise noted. The information in this snowpack summary is provided by the USDA Forest Service who is solely responsible for its content.
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