Refrozen surface snow below treeline will provide a smooth surface for avalanches triggered in the alpine. Reactive windslabs may run farther than expected. Watch out for solar triggered avalanches when the strong spring sun shines.
Weather Forecast
A mix of sun and cloud today with an alpine high of -7 and freezing levels hovering around 1200m. Moderate southerly winds will continue. Expect the weather to be unsettled, with convective cells bringing scattered flurries or rain showers at lower elevations. Snowfall amounts between trace and 5cm.
Snowpack Summary
Strong south winds overnight contributed to loading and wind slab formation in the alpine. Yesterday's freezing level climbed to 2300m, creating a melt-freeze crust on the surface. Isolated surface hoar has been found in protected areas down 20cm. The snowpack is moist blow treeline and is being held together by several near surface crusts.
Avalanche Summary
A natural avalanche cycle accompanied this morning's strong winds. Several large size 2-3 avalanches were observed in the highway corridor east of Rogers Pass from steep terrain on Mt Tupper and Mt MacDonald. These slides ran into the valley bottom, assisted by the smooth surface crust at lower elevations.
Confidence
Intensity of incoming weather systems is uncertain
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.