Avalanche Forecast

Issued: Mar 13th, 2018 4:06PM

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

Avalanche Canada mgrist, Avalanche Canada

Isolated wind slabs at higher elevations are the main concern right now. Remain vigilant around cornices, and minimize overhead exposure.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain on Wednesday

Weather Forecast

We're looking at small amounts of new snow and slightly warmer than normal temperatures throughout the forecast period. Scattered convective activity on Thursday and Friday could result in locally higher snowfall totals.WEDNESDAY: Cloudy with wet flurries in the afternoon (5 cm, with 10 cm possible in the Monashees). Light to moderate south west winds. Freezing level falling to 1700 metres late in the day, with alpine high temperatures of +2.THURSDAY: Scattered flurries (2-5cm possible). Light northerly winds. Freezing level around 1700 metres with alpine high temperatures around 0 degrees.FRIDAY: Scattered flurries (2-5cm possible). Light north / east winds. Freezing level 1700 metres with alpine high temperatures of 0 degrees.

Avalanche Summary

A widespread natural avalanche cycle to size 3 was reported over the past four days. These were primarily wet loose avalanches on sunny aspects; however, on Saturday some did step down to the mid-February layer (with 50-70 cm crowns) on southerly aspects. Large cornice falls were also reported on the weekend.

Snowpack Summary

The main story over the past several days has been the sun's effect on south and west facing slopes. Daytime heating has resulted in moist or wet snow on sunny aspects, freezing to form a crust overnight. On north and east facing slopes, cold dry snow can still be found and it sits on a well-settled snowpack. Deeper persistent weak layers from January and December are generally considered dormant, but could wake up with a surface avalanche stepping down, cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs formed during last week's storm and may remain reactive - their distribution is variable. Extra caution is needed on solar aspects where sunshine could act as a natural trigger and buried sun crust as a sliding layer.
Watch for wind loaded pockets near ridge crests and roll-overs.Use ridges or ribs to avoid pockets of wind loaded snow.Pay attention to cornices and give them a wide berth when traveling on or below ridges.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Mar 14th, 2018 2:00PM