Avalanche Forecast

A major warming event is forecast for Thursday with freezing levels climbing to around 2500 m. A storm system is expected to arrive Thursday night which will replace the warm air and linger into Friday morning. 

Wednesday Night: Mainly cloudy, moderate to strong SW wind, freezing level climbing to around 1800 m. 

Thursday: Mainly cloudy in the morning, sunny breaks in the afternoon, strong to extreme SW wind, freezing level high around 2500 m.

Thursday night: Precipitation 5-10 mm, strong to extreme SW wind, freezing level 2000 m dropping to around 1200 m.

Friday: Snowfall 5-10 cm in the morning, sunny breaks in the afternoon, moderate NW wind, freezing level high around 1300 m.

Saturday: A mix of sun and cloud in the morning, light snowfall in the afternoon, moderate to strong NW wind, freezing level high around 800 m.

On Tuesday, the Avalanche Canada field team observed a size 1.5 storm slab on a north aspect which was expected to have occurred near the end of the storm on Monday. This MIN report describes numerous size 1-2 storm slabs which had occurred during the storm, primarily on northwest through east aspects resulting from wind loading.  

Observations are very limited this time of year. If you are getting out in the backcountry, please consider sharing your observations to the Mountain Information Network. 

The recent storm is estimated to have produced 60-100 cm of new snow. This storm snow has buried a widespread, supportive melt-freeze crust. Recent observations suggest the new snow is relatively well bonded to this underlying crust but it still has the potential to be a sliding surface for storm slab avalanches during the upcoming warming event. Strong to extreme southwest wind during the storm had redistributed this storm snow in exposed, high elevation terrain forming touchy wind slabs and building large cornices. 

Reports from Tuesday suggest the recent storm snow remains mostly unconsolidated in sheltered terrain. With sun on Wednesday and major warming on Thursday, the storm snow is expected to settle rapidly and form a more cohesive slab which is expected to increase the avalanche danger in the short term. 

The middle and lower snowpack are generally strong and well bonded.

• Watch for changing conditions today, storm slabs may become increasingly reactive.
• The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
• Remember that in the spring strong solar radiation and warm temperatures can weaken the snow in a matter of minutes.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.