Confidence
Fair - Forecast snowfall amounts are uncertain on Sunday
Weather Forecast
Overnight and Sunday: Light snow overnight should accumulate another 5 cms by morning and another 5-10 cms during the day on Sunday. Moderate to strong Southwesterly winds overnight should become moderate Southwesterly with strong gusts during the day.Monday: Strong Southwest winds are forecast to build as the next pulse of moisture moves in from the coast. Expect 10-15 cms with temperatures down to about -9.0 in the alpine.Tuesday: Another pulse of moisture should bring 10 cms more during the day combined with moderate Southwest winds.
Avalanche Summary
Loose snow avalanches (sluffing) continue to be reported from steep terrain.
Snowpack Summary
Thin layers of dry cold snow are accumulating each day. In some areas this new snow has been transported into wind slabs. The recent cold and dry weather has caused the surface snow to facet and become weakly bonded. There has also been some surface hoar growth, mostly at and below treeline that has resulted in a weak bond below the new snow. This weak bonding has resulted in dry loose snow sluffing out of steep terrain. Forecast new snow on top of this weak unconsolidated surface should continue to sluff easily. If the new storm snow develops into a consolidated slab above the weak surface layers, expect this slab to be easy to trigger by light additional loads. If the new snow is transported into a wind slab, expect those pockets of wind slab to be very reactive; they may fail naturally or be triggered from adjacent terrain.
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.