Avalanche Forecast

Issued: Apr 24th, 2019 4:03PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Loose Wet.

Avalanche Canada jsmith, Avalanche Canada

Strong solar radiation may increase the likelihood of triggering lingering winds slabs on lee features below alpine ridgetops. Any appearance of the strong April sun can initiate a loose wet avalanche cycle.

Summary

Confidence

Low - Due to the number of field observations

Weather Forecast

WEDNESDAY NIGHT: Clear / Light to moderate, westerly winds / Alpine low -11 C / Freezing level Below valley bottom.

THURSDAY: Sunny / Light, westerly winds / Alpine high -3 C / Freezing level 1800 m.

FRIDAY: Mix of sun and cloud / Light, westerly winds / Alpine high -1 C / Freezing level 1700 m.

SATURDAY: Cloudy with alpine flurries; 5-10 cm. / Light, northwesterly winds / Alpine high -5 C / Freezing level 1200 m

Avalanche Summary

No new avalanches were reported in this region on Tuesday. However, there are currently very few professional observers submitting daily observations. Please submit your observations to the MIN. Photos of avalanches or current conditions are particularly useful.

On Sunday, numerous solar triggered avalanches initiating below alpine ridgetops up to size 3 were reported.

Check out this MIN report of a notable human triggered size 2.5 avalanche that occurred on Saturday HERE.

On Friday, a widespread storm slab natural avalanche cycle to size 3 occurred on all aspects in the alpine. This new snow will need several days to settle and bond to the old snow surface.

Snowpack Summary

5-10 cm. of new snow sits on a crust everywhere except high north facing terrain. Wind slabs created by last weeks storm may still linger in lee terrain below ridgetops. A layer of surface hoar (weak, feathery crystals) in the upper snowpack could still be reactive to human triggers in isolated locations such as high elevation, north facing terrain.

Below treeline, snow is disappearing rapidly.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong solar radiation may increase the likelihood of triggering lingering winds slabs on lee features below alpine ridgetops

  • Use small slopes without consequence to test the bond of the recent snow.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Pay attention to changing conditions with elevation/aspect.

Aspects: North, North East, East, South East, North West.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Strong solar radiation may trigger loose wet avalanches on steep terrain; especially at upper elevations where there is new snow.

  • Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.
  • A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.
  • Cornices become weak with daytime heating, travel early on exposed slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Apr 25th, 2019 2:00PM