Avalanche Forecast

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A weak weather system is expected to arrive on Wednesday morning. 2-4mm of precipitation is forecast on Wednesday with freezing levels reaching around 1400m in the afternoon and near valley bottom overnight. Alpine winds are expected to be strong from the southwest. A more substantial system is expected to arrive on Thursday and 10-15mm of precipitation is forecast between Thursday afternoon and Friday afternoon. Freezing levels are expected to fluctuate between 1000 and 1500m and alpine winds should remain strong from the southwest.

Avalanche observations are very limited at this time of year but there is enough snow for avalanches above around 1700m elevation. The recent storm snow (~25cm) is reported to be reactive to snowpack tests and shooting cracks have been observed in this layer. Wind slabs are expected to be a concern right now and if more new snow accumulates, a more widespread storm slab problem has the potential to develop. If you are out in the mountains, please send us your observations.

Early season snowpack observations are still very limited in the region but the threshold for avalanches has been exceeded at treeline and in the alpine. Reports suggest that the snow depth at treeline is 110-150cm. Around 25cm of recent storm snow is reported to be reactive to snowpack tests and shooting cracks have been observed. The crust from the middle of November is down 50-80cm and the crust from early November is down 80-110cm. The snowpack tapers off drastically below treeline and below around 1700m there is not yet enough snow for avalanches.  On the western side of the Lizard Range, the snowpack depth is reported to be 40cm at 1800m elevation.