Avalanche Forecast

Fair - Timing, track, or intensity of incoming weather system is uncertain

A weak storm system will bring light precipitation to the region on Wednesday night and Thursday. Models are currently showing 10-15mm for much of the region. Unfortunately freezing levels are expected to stay around 1800m so much of this precipitation will fall as rain. Alpine winds on Thursday are forecast to be strong from the SW to W. On Friday, a ridge of high pressure should bring a mix of sun and cloud. Freezing levels are forecast to be over 2500m on Friday and alpine winds moderate from the SW. Unsettled conditions are expected on Saturday as a storm system moves into the region. Light precipitation is expected and winds are forecast to become strong from the SW.

On Tuesday, remotely skier-triggered avalanches up to size 2 were reported from as far as 40m away. These were releasing on the mid-February weak crust/facet layer and typically occurred in wind loaded areas. On Thursday, light rain at lower elevations may further destabilize the warm upper snowpack and loose wet avalanches should be expected. Up high where the new precipitation falls as snow, wind slab formation is expected to continue. Finally, with the combination of unseasonably warm temperatures with little overnight recovery, recent strong solar inputs, and forecast rain, there is a concern for dormant persistent weak layers to wake-up which could result in large slab avalanches. This is a low probability, high consequence problem but deserves attention as we can expect several more days of warm conditions.

A moist snow surface is being reported to around 2500m on solar aspects and around 2000m on north aspects. Up to 40cm of recent snow is settling into a cohesive slab with the unseasonably warm conditions. Strong winds transported the new snow into deep wind slabs in leeward terrain features. The new storm snow is sitting above loose facetted snow and a melt-freeze crust that was buried in mid-February. The late-Jan crust/surface hoar layer (up to 100 cm deep) and the mid-January surface hoar (80-120 cm deep) have gained significant strength and have been dormant for several weeks but now have the potential to wake-up with the current warm temperatures.