Avalanche Forecast
Issued: Apr 17th, 2019 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
timothy johnson,
Parks Canada
ROAD CLOSURE: The Icefields Parkway (93N) is likely to be closed due to increased avalanche hazard on Thursday afternoon to Saturday morning from Parker Ridge to Saskatchewan Crossing. For updates check: https://511.alberta.ca
Summary
Weather Forecast
For the Parker Ridge Area:
Thursday:
Periods of snow: 15cm (rain below treeline)
Treeline temperature: High 0 C.
Ridge wind southwest: 20 km/h gusting to 50 km/h.
Freezing level: 2300 metres.
Snowpack Summary
Above treeline 15-20cm of settling snow sits on a variety of crusts. Above 2200m on northerly slopes, a more winter like snowpack can be found, with windslab, a peristent weak layer down 20-50cm and a facetted mid and lower snowpack which is weak in shallow areas.
Avalanche Summary
There was natural windslab activity observed in the past couple of days. The mid march PWL continues to produce whumphing in shallower snowpack areas and on moraine features, indicating unstable snow below.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Friday
Problems
Persistent Slabs
Snowpack tests and whumphing would suggest that a weak layer of facets persists down 20-50cm in some areas. This layer will likely become reactive with loading from forecasted snow on Friday. Use caution specifically in shallow alpine features.
- Whumpfing is direct evidence of a buried instability.
- Avoid shallow snowpack areas where triggering is more likely.
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Wind Slabs
Windslabs are likely forming treeline and above with strong SW winds and new snow.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 18th, 2019 4:00PM
