Main concerns: Wind Slab, Loose Wet, Cornice Fall.
Summary
Travel & Terrain Advice
Avoid travel in avalanche terrain during the peak of the next storm system. Avoid wind loaded features and convex rolls, especially at ridge top. Give growing cornices a wide berth when travelling both above and below them.
Avalanche Summary
Widespread small human triggered loose dry avalanches observed on Tuesday afternoon. These avalanches were triggered from all sufficiently steep terrain at treeline and below treeline.
Snowpack Summary
A brief lull in the storm parade produced widespread surface hoar development on many aspects at all elevations Sunday and Monday. These weak feathery crystals formed on top of settling recent storm snow. With the incoming storm system, this weak layer of snow will be buried in sheltered terrain at all elevations. Below these layers, old storm snow is beginning to settle and bond well to adjacent layers which include a thick strong crust. Some weak sugary facet crystals have formed around this crust, but have not shown evidence of reactivity. With incoming snow load and rising freezing levels, a very large trigger on a large alpine feature could potentially awaken deeper instabilities and produce very large avalanches.
Snowpack Details
Surface: 20-40 cm of new low density storm snow. Upper: A thick crust and weak buried surface hoar layers. Mid: Settling old snow and some unreactive crusts. Lower: well settled.
Past Weather
Clear and calm conditions on Monday across the forecast region followed by the arrival of the next vigorous Pacific frontal system Tuesday morning. Outflow winds were strong from the NE veering to strong to extreme from the SE with the onset of precipitation. Approximately 20-30 cm of new low density snow fell through the day Tuesday and was transported into lee terrain by strong SE winds.
Weather Forecast
WEDNESDAY: 50-80 mm of precipitation with freezing levels rising to around 1600 m. Strong winds from the SE. THURSDAY: 30-60 mm of precipitation with freezing levels around 1500 m. Strong winds from the SE. FRIDAY: 10-15 mm of precipitation with freezing levels around 1650 m. Winds strong easing to moderate from the SE.
Confidence
Moderate - Uncertainty in precipitation intensity and freezing levels.