Wednesday February 14, 2018
Cornice Fall, Wind Slab
Travel & Terrain Advice
Minimize overhead exposure during periods of heavy loading from new snow and wind
Avoid freshly wind loaded features
No new natural avalanches reported, no explosive avalanche control conducted.
New snow, moderate south and north wind all falling on hard and well developed crust. Expect to find wind slab avalanches on all aspects and in the alpine and tree line. Expect new snow to bond poorly to the old crust.
Cornices can be found on north aspects at both the treeline and the alpine. Cornices will build through this forecast period and new cornice noses will become touchy to human triggering. If triggered these could produce an avalanche big enough to bury injure or kill a traveler. Take the time to identify these features and ensure a wide berth when travelling either above or below these features.
New snow and moderate winds from both the south west and north east will form hazardous winds slab on all aspects and will be found in both the alpine and at tree line. Expect these avalanche to be touchy to light triggers such as skier traffic and when triggered will run fast and far.
During the overnight period,light new snowfall of up to 15 cm will bury a well developed melt freeze crust found on all aspects and elevations. Isolated areas protected from both the sun and wind below tree line had very small surface hoar and its likely this will be buried. Below this upper melt freeze crust well settled and dense snow continues to strengthen.
|Surface||10-15 cm new snow|
|Upper||hard melt freeze crust|
A period of cool and clear conditions with temperatures in the alpine falling to below -10. Winds from the north west persisted and built during daytime to moderate.
During the initial overnight period of this forecast, all mountainous terrain zones within the forecast area will receive up to 15 cm of new snow. Moderate south west winds will accompany the storm with temperatures remaining cool. In the storms wake, north west winds will ramp up to moderate, skies will clear and temperatures will warm with freezing levels rising to 1000 m.
Another storm arrives Friday with continued cool temperatures and light to moderate snow fall.
Wednesday 5-15 cm of overnight snowfall becoming clear in the am temps -3 to -1, moderate Sw becoming Nw, freezing level 200 m rising to 900 m mid day.
Thursday 5 cm light snowfall temps -6 rising to 0, winds light Sw, freezing level 0 m rising to 1000 m mid day.
Friday 5- 10 cm of moderate snowfall , temps - 3 to 0 , winds light to moderate Sw, freezing level 600 m rising to 1400 m.
Posted on Wednesday February 14, 2018 by Jesse Percival