We’re on the brink of the first significant storm in a while. The avalanche hazard is expected to rise throughout the weekend, with the peak intensity expected on Sunday.
A combination of older stubborn wind slabs and newly forming slabs is overlaying a heavily faceted snowpack. As new snow accumulates and strong to extreme winds continue through the day, we expect this issue to become more reactive.
Wind speeds are expected to exceed 100 km/h on Saturday. We anticipate this will trigger the heavily faceted snowpack, leading to loose dry avalanche activity in steep terrain.
A fatal avalanche that occurred south of Golden on Monday. A small windslab on a north aspect at 2300 m carried one person a long way (1000 m) down a steep, confined gully with many terrain obstacles.
No new avalanches were reported or observed in the Little Yoho region region Friday.
We are anticipating a wide spread avalanche cycle starting Saturday night with the incoming storm.
Aging wind slabs and surface facets sit on top of the Jan 30 interface. Specific areas exposed to the wind may also have strastrugi. The mid-pack is generally weak facets, while depth hoar over a crust forms an even weaker base. The snowpack is the weakest in eastern areas where snow depths are low. In these areas, the basal weaknesses should be carefully considered.
A Pacific frontal system is expected to reach the forecast region on Saturday. Snow accumulation is forecasted to range from 15 to 40 cm, depending on the weather model. The storm will peak in intensity on Sunday night. In addition to snow, freezing levels will rise to 2000m, with wind speeds at ridge crests reaching up to 100 km/h.
