Avalanche Canada jsmith, Avalanche Canada

Kootenay Boundary Avalanche Forecast

Apr 23rd, 2019 3:37PM

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

If temperatures remain warm, rain soaked wet slabs releasing on crust layers are still possible.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TUESDAY NIGHT: Partly cloudy / Light, westerly winds / Alpine low -1 C / Freezing level 2000 m.

WEDNESDAY: Mix of sun and cloud / Light, northwesterly winds / Alpine high 4 C / Freezing level 2100 m.

THURSDAY: Sunny / Light, southwesterly winds / Alpine high 5 C / Freezing level 2300 m.

FRIDAY: Cloudy with isolated rain showers; 1-3 mm / Light, southwesterly winds / Alpine high 3 C / Freezing level 2000 m.

Avalanche Summary

No new avalanches were reported in this region on Monday. 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 Saturday, natural and skier triggered loose wet avalanches to size 1.5 were reported on all aspects at treeline and above.

Snowpack Summary

Rain to mountain-tops Thursday night soaked 20-40 cm of recent snow and initiated a loose wet avalanche cycle at treeline and above on Friday. Below treeline, the snow is isothermal (0 C throughout the snowpack) and disappearing rapidly.

As temperatures cool, we will enter a diurnal cycle during which the hazard will be low in the mornings, if there was a strong overnight freeze, and elevate throughout the day depending on warming and solar radiation. Hazard ratings are for the peak hazard expected during each day.

Problems

Wet Slabs

An icon showing Wet Slabs

Likelihood

Possible

Expected Size

1 - 2

If temperatures remain warm, wet slabs releasing on crust layers are still possible.

  • If the snow is wet, mushy, or feeling bottomless, its time to go home.
  • Pay attention to changing conditions with elevation/aspect.

Aspects:

East, South East, South, South West, West.

Elevations:

Alpine, Treeline.

Loose Wet

An icon showing Loose Wet

Likelihood

Possible

Expected Size

1 - 1.5

If temperatures remain warm and the solar radiation is strong, loose wet avalanches are still possible.

  • 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:

All aspects.

Elevations:

Alpine, Treeline.

Valid until: Apr 24th, 2019 2:00PM