Avalanche Forecast

Issued: Apr 19th, 2014 3:00PM

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

jeremy.mackenzie, Alberta Parks

Kananaskis.

Sunday should be a bit cooler, but pay attention to the temperatures and radiation. Start early and finish early! Mon and Tues will see a spike in hazard due to very high freezing levels both days and rain to mountain top on Tuesday.

Summary

Confidence

Good - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Sunday should bring a slightly cooler day with gusty west winds and freezing levels near 1900 metres. Monday will be hot with freezing levels climbing to 3000 metres. Tuesday may bring some rain and freezing levels near 3000 metres.

Avalanche Summary

A few naturally triggered and cornice triggered slides have been observed today. Theses avalanches ranged in size from 1.5 to 2.5 and were all associated with the warming trend or solar radiation. All of the avalanches observed today stepped to the basal facets and went full depth.

Snowpack Summary

Up to 10cm of snow fell overnight, but this quickly settled through the day due to warm temperatures. Crusts are melting during the day and re-forming each night, except on North aspects at higher elevations. Thin wind slabs can be found in the immediate lees of ridgelines at higher elevations. The basal facets and depth hoar are a concern when the temperatures rise and the solar radiation is strong. There is potential for large full depth avalanches due to this basal weakness.

Problems

Deep Persistent Slabs

As temperatures warm through the day and solar radiation increases, the basal weak layers are becoming reactive. Full depth avalanches have been observed in recent days, some of which have been triggered by cornice failures.

Minimize exposure to sun exposed slopes when the solar radiation is strong.>Be aware of thin areas that may propogate to deeper instabilites.>Extra caution needed around cornices with current conditions.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

3 - 6

Loose Wet

Solar triggered avalanches are occurring on SE through W aspects with regularity. Warming is also a concern on all aspects at lower elevations.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Wind Slabs

Thin wind slabs are found in the immediate lees of ridgelines. These slabs are generally not bonding well to the crusts underneath.

Avoid freshly wind loaded features.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 20th, 2014 2:00PM