Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Below Threshold.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Below Threshold.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Below Threshold.
Regions
South Rockies.
Check out the South Rockies Blog for thoughts on early season forecasting in this region. If you have recent observations please send them to [email protected]
Confidence
Poor - Due to the number of field observations
Weather Forecast
Synopsis: The current pattern persists through the forecast period. On Wednesday a weak frontal system should clear out the inversion. No significant change in the weather for the forecast period.Tuesday: Freezing Level: Near 0 C at Valley Bottom, above freezing layer from 1500 - 3000m. Precip: No significant precip expected. Wind: Light SWWednesday: Freezing Level: 1200m Precip: No significant precip expected. Wind: Light, Variable.Thursday: Freezing Level: Valley Bottom Precip: No significant precip expected. Wind: Light, SW switching to Moderate W in the late afternoon.
Avalanche Summary
The last reported avalanche activity was during the tail end of the storm on Tuesday Nov 19th. If you see or trigger an avalanche, please send us a note at: [email protected]
Snowpack Summary
Observations from this region are EXTREMELY limited at the moment!Treeline snowpack depths in sheltered areas vary between approximately 40-80 cm. Since the snow stopped falling on Nov 19th it has been subjected to strong wind, cold temps and chinook driven warming. As a result it should be easy to find wind scoured snow, old windslabs, temperature crusts & facet formation in a single day's ride or tour.A crust or significant density change may exist around 40 cm below the surface. This has been reported to have weak faceted crystals above and below, and produces sudden "pop" results in compression tests. Below this near the base of the snowpack, an earlier crust buried in October lies close to the ground. This layer may still be of concern on isolated smooth terrain features that have not seen avalanche activity.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.