Avalanche Forecast

Issued: Mar 9th, 2018 4:46PM

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

Lisa Paulson, Parks Canada

Little Yoho.

This is our first big warmup - the hazard will be Low in the morning and rise to Considerable on solar aspects. Northern aspects will stay at a lower hazard. Cornices overhead may start to fail, and could potentially trigger deeper layers.

Summary

Weather Forecast

Our first major warming trend will occur over the next several days. Expect sunny skies and temperatures to get incrementally warmer with each day, peaking on Tuesday/Wednesday. For Saturday, expect treeline highs to be around -3C, winds light from the SW and freezing levels to be around 1600 m.

Snowpack Summary

Very little wind effect overall except in the high alpine. Sun crust on steep solar aspects is forming. Generally, 10-20 cm of snow sits over a firm mid-pack. The Jan surface hoar layers down 100-150 cm are inactive in tests. In shallow areas the deeper facet layers are currently dormant, but could become active with the warm days ahead.

Avalanche Summary

No new avalanches reported in Little Yoho, but suspect there may have been some loose wet avalanches at lower elevations from steep solar rocky terrain with prolonged sun affect.

Confidence

Problems

Loose Wet

Climbers avoid terrain exposed to the sun, we expect solar related avalanche activity over the next few days with prolonged sun affect and warmer day time temperatures. Loose wet avalanches can be expected to initiate from overhead rocks and cliffs.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2

Wind Slabs

Increasing West winds have moved new snow around in the alpine forming small slabs in lee areas. Watch for these in the high alpine, especially in steep unsupported terrain where skier triggering may be possible.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Mar 10th, 2018 4:00PM