West Central Montana Avalanche Center

Area of observation is closed to public traffic December 1 - March 15 for Winter wildlife protection

Observations taken in an area closed to public traffic December 1-March 15 for Winter wildlife protection. Area is representative of higher elevation start zones on the west slope of Mt Jumbo.

Found a generally stable snowpack. We dug a pit looking for persistent problems. None were found in this area.

This pit is not typical of the snowpack in most areas of the Rattlesnake.

Objective of finding condition of faceted layers 100cm deep in snowpack on northerly slopes and likelihood of propagation. This targeted layer did not react in extended column test. Propagation Saw Test showed possibility for this later to propagate, though not likely in this snowpack.

After a dry and mild fall, Montana and Idaho entered winter, receiving 70-100cms (2-3 feet) of snow in the past 5 days in the Lost Trail Pass area. The storm has settled well most locations, however there is a layer of concern on steeper, shaded, northerly aspects above 7500'. Test results showed propagation around a meter down in two study pits 145cm deep (ECTP22 @47cm SC/Q1; ECTP28@47cm SC/Q1). Though generally conditions are good, keep an eye on those slopes. And be aware, early season conditions still persist !