A constant stream of moist air will bring light amounts of new snow with sufficient wind to blow things around. Continue the program: avoid wind slabs on steep slopes.
Recent winds have blown from the south, southwest and northwest. As a result, expect wind slabs to have formed on north-, northeast- and southeast-facing slopes.
Wednesday night: 2-4 cm new snow. Moderate southwesterly winds.
Thursday: 3-5 cm new snow. Moderate westerly winds becoming northwesterly in the afternoon. Temperatures around -10 C.
Friday: 2-4 cm new snow. Moderate southerly winds. Temperatures around -12 C.
Saturday: Around 5 cm new snow. Moderate southwesterly winds. Temperatures around -11C.
Since the highway has been closed for avalanche control almost since the last forecast, it is not known whether avalanches occurred in the White Pass area during Monday's storm. While the paths above the highway south of Carcross have a modified snowpack due to avalanche control, significant natural and explosive controlled activity here gives a clue as to what likely happened closer to the Pass.
With relatively light amounts of new snow but ongoing winds, I anticipate human-triggered wind slab avalanches to be of concern throughout the forecast period.
Recent new snow has been redistributed by winds blowing from the south to northwest directions. Wind effect is widespread in exposed areas. Snowpack tests indicate the mid-pack near White Pass is reasonably strong with no persistent weak layers. This suggests the upper storm and wind slab layers should be the main focus of concern at this time. There is reported to be excellent powder and riding in more wind protected / sheltered areas.
Snow depths at White Pass are around 160 cm at our wind protected Fraser study plot. Deeper locations (higher terrain west of the highway) have more than 200 cm, while on the east of the highway depths are around 185 cm. It's reasonable to expect a thin snowpack composed mainly of sugary facets in the Wheaton Valley, and thinner wind-scoured alpine areas.
