A highly anticipated change is on the horizon as weather models continue to advertise a significant pattern shift and snowfall to begin tonight. By Tuesday morning, if the forecast verifies, we expect avalanche conditions to change and danger to ramp up more by the end of the week. The amount of new snow received and wind accompanied with the two storms forecasted will keep us on our toes each day as this evolves. The snowpack throughout the Southern Mountains is queued up for potentially the first real tolerance test of the season as November was not a big moisture producer.
The majority of our snowpack, accumulated in the month of October is now faceted and weak at the surface and also within the pack on northerly-facing slopes. Above treeline, east and west aspects offer firm- crusted surfaces overlying weak-faceted snow and older crust layers below. Time will tell, but it will likely not take much of a new load to produce avalanches that step deeper into the foundational snowpack.
In addition, the snow on north-facing slopes, near and below treeline is also very weak. Those slopes hold loose, cohesionless snow from the surface to the ground. This lack of structure becomes more problematic on steep rolls or creek banks where the weak surface facets are likely to sluff from the weight of a rider and will gain mass while moving downhill. We expect these facet sluffs to remain small in size, but if caught, the consequences could yield a rough ride through shallowly buried obstacles.
Although the start to the season appears bleak, keep in mind that bare ground or patchy snow-covered terrain provides a clean slate. Those slopes will not have old snow layers lurking below and should offer safer options as new snowfall is added. Patience and careful terrain selection will be crucial moving forward this week and awhile beyond.