Avalanche Forecast
Issued: Mar 17th, 2020 5:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Wind Slabs and Persistent Slabs.
MBender,
Avalanche Canada
A ridge of high pressure has set in for the forecast period. Expect to see mainly sunny skies. Minimize exposure to steep slopes facing the sun during the hottest part of the day.
Summary
Confidence
High - Confidence is due to a stable weather pattern; little change is expected for several days.
Weather Forecast
TUESDAY Night: Mostly clear, light northwest wind, alpine temperature -8 C.
WEDNESDAY: Mix of sun and cloud, light to moderate northwest wind, alpine temperature -3 C, freezing level 1800 m.
THURSDAY: Mix of sun and cloud, light west wind, alpine temperature -4 C, freezing level 1700 m.
FRIDAY: Mix of sun and cloud, light northwest wind, alpine temperature -5 C, freezing level 1600 m.
Avalanche Summary
Avalanche activity on Monday was reported as natural loose dry or loose wet avalanches size 1-2 running in steep terrain facing the sun in the alpine.Â
Reports from the weekend show several natural wind slab avalanches ranging in size from 1.5 to 2.5 running in the alpine on east, southeast and north aspects at treeline and in the alpine. There were also two reports of natural size 2 and 3 persistent slab avalanches running on the late February surface hoar layer. These were on west and southwest aspects between 1700 m and 2200 m and were 50-100 cm deep.Â
Snowpack Summary
Recent moderate to strong northeast wind has created widespread wind effect in exposed terrain. With recent sun and relatively warm temperatures expect to find either moist surface snow or crust on slopes facing the sun. 30-50 cm of new snow from last week may sit on a surface hoar layer and/or a sun crust on steep solar aspects.
A widespread weak layer of surface hoar is buried 60-120 cm deep. On solar aspects, this layer may sit over a crust. There is a low likelihood of triggering an avalanche on this layer, but the consequences of doing so would be high. Read more about surface hoar on our forecaster blog.
Terrain and Travel
- If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
- Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
- Be aware of the potential for large avalanches due to the presence of buried surface hoar.
- Cornices become weak with daytime heating.
Problems
Loose Wet
Expect loose dry or wet avalanches to run in steep terrain facing the sun during the heat of the day.
Aspects: South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Lingering wind slabs from recent moderate to strong northeast winds may still be reactive to human triggering.
Aspects: South East, South, South West, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
A weak layer of surface hoar is buried 60-120 cm deep and is still sensitive to triggering in specific areas. Although this problem can be found on all aspects and elevations, north to east aspects near treeline have been a hot-spot for reactivity.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 18th, 2020 5:00PM
