Wednesday February 21, 2018
Cornice Fall, Wind Slab
Travel & Terrain Advice
Seek low angle terrain and areas shelter from the wind.
Ensure a wide berth when travelling either above or below cornices
On Tuesday explosive testing produced small results size one loose on a north east aspect at tree line . This feature was wind loaded and unsupported but did not perform as expected. No new natural avalanches observed.
Cornices are large and can be found on north aspects at both the treeline and the alpine. 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 them.
Winds slab will predominantly be found on lee aspect but will as well be found on cross loaded features that face the wind. Touchy to human triggers, these avalanches once initiated will produce large avalanches , size two.
Variety of surface conditions as a result of strong predominantly north wind, exposed ridge top areas scoured to the valentines day crust and in protected areas the crust can be found down an average of 40 cm.The crust and new snow are bonding moderately well, The crust is thick and very strong, below this the mid and lower snow pack is settled and dense
|Surface||new low density snow|
|Upper||melt freeze crust from 30 to 90 cm thick|
Cool temperatures, clear skies and moderate north west wind.
A mass of arctic air dominates the region with the occasional disturbance descending from the north bringing to the forecast area some light precipitation. Freezing levels and temperatures are expected to remain low. North winds will continue to be light to moderate.
Wednesday 0 to 5 cm new snowfall temps -12 to -4, winds moderate north west, freezing level 0 m rising to 800 m mid day.
Thursday no new snowfall temps -12 rising to +1, winds moderate west, freezing level 0 m rising to 200 m mid day.
Friday no new snowfall temps -5 to 0 winds light to moderate north west , freezing level 250 m rising to 1000 m mid day.
Posted on Wednesday February 21, 2018 by Jesse Percival