Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Strong winds Tuesday and Wednesday have produced wind slabs in isolated locations at ridgetop.
The warmer and sunnier it becomes Thursday, the higher the hazard. Our hazard rating is for the highest potential hazard for the day.
The likelihood of triggering an avalanche on the Jan 24 surface hoar layer will increase as the overlying slab becomes thicker or denser.
Strong winds Tuesday and Wednesday have produced wind slabs in isolated locations at ridgetop.
A surface slab over hard surfaces and/or surface hoar is a developing problem that could catch users off guard as it is likely susceptible to human triggering. Avoid unsupported and steep open slopes where this problem may exist.
Clear skies and warm air will elevate freezing to ridgetop and higher on southerly aspects. Wet loose avalanches are possible the warmer and more sun we get, particularly proximate to southerly rock outcrops.
Several loose wet up to size 1 on steep south aspects. Debris from a recent size 2.5 (last 48 hours) was observed out of the north side of Mt. Stephen Tues. A size 2 out of the SE side of Brewster rock near Sunshine was also observed Tuesday.
Over the weekend multiple avalanche involvements were reported, up to size 2, all running 10-25 cm deep on the surface hoar/crust layer.
Your MIN reports are very useful when building our forecasts. Thank you all for past and future submissions
Dry and moist snow depending on elevation and aspect (10-30cm) overlies the Jan 24th surface hoar, crust and/or previously wind affected snow. This surface snow is consolidating into a slab with warm temperatures and wind.
Widespread previous wind affect in alpine and exposed areas at treeline.
Thursday: Sunny with cloudy periods. Alpine temperature: High 2 °C. Mostly light ridge wind occasionally gusting to 30 km/h. Freezing level: 2900 meters.
Friday: Sunny. Alpine temperature: Low -1 °C, High 1 °C. Mostly light ridge wind occasionally gusting to 45 km/h. Freezing level: 2600 meters.
Saturday: A mix of sun and cloud. Alpine temperature: Low -3 °C, High -1 °C. Freezing level: 2200 meters.