Avalanche Forecast
Issued: Apr 19th, 2019 4:48PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
jsmith,
Avalanche Canada
Fresh storm slabs at upper elevations will likely be reactive to human triggers; especially in lee features below alpine ridgetops.
Summary
Confidence
Moderate - Due to the number of field observations
Weather Forecast
FRIDAY NIGHT: Clearing / Light to moderate, northwesterly winds / Alpine low -6 C / Freezing level 1200 m.
SATURDAY: Sunny / Light, northwesterly winds / Alpine high -2 C / Freezing level 1800 m.
SUNDAY: Sunny / Light, southwesterly winds / Alpine high 1 C / Freezing level 2200 m.
MONDAY: Cloudy / Moderate, southwesterly winds / Alpine high 0 C / Freezing level 2100 m.
Avalanche Summary
No new avalanches were reported on Thursday.
On Tuesday, numerous naturally triggered size 2 persistent slab avalanches were reported on all aspects in the alpine.
Snowpack Summary
10-25 mm of rain has soaked the snowpack below treeline. The rain/snow boundary on Friday was around 2000 m. New snow amounts in the alpine will taper rapidly with elevation and likely equate to around 10-15 cm of moist snow at upper elevations adding to the 15-40 cm recent snow which overlies a crust everywhere except high elevation, north facing terrain where preserved surface hoar (weak, feathery crystals) may be present in isolated locations down 40-60 cm. A similar layer buried in early April is down 50-80 cm. Smaller storm slab avalanches may step down to one of these deeper weak layers.
Below treeline, snow is disappearing rapidly.
Problems
Storm Slabs
Fresh storm slabs at upper elevations will likely be reactive to human triggers; especially in lee features below alpine ridgetops.
- Pay attention to changing conditions with elevation/aspect.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Use small slopes without consequence to test the bond of the recent snow.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Loose Wet
If temperatures remain warm and the solar radiation is strong, loose wet avalanches are still possible at treeline and likely in the alpine where there is new snow.
- A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.
- Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.
Aspects: East, South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 20th, 2019 2:00PM
