Summary
Confidence
Good
Weather Forecast
As the low off the Oregon coast moves inland and South, light-moderate snowfall amounts are expected through Thursday. The low deteriorates by Friday morning and is being replaced by a ridge, bringing dry, sunny conditions with very little wind. Overnight into Thursday: Light-moderate snow accumulations. Ridgetop winds will blow light from the East. Alpine temperatures near -4 and freezing levels at 1300 m.Friday and Saturday: Ridgetop winds will remain light from the NE switching to the West on Saturday. Alpine temperatures near -4 and freezing levels rising to 1500 m in the afternoon then falling to valley bottom overnight.
Avalanche Summary
On Tuesday a couple of skier triggered avalanches occurred on Southerly aspects above 2000 m. These were reported to fail on the early March facet/crust interface which currently has about 25 cm of snow sitting above it. No new natural avalanches have been reported.
Snowpack Summary
In much of the region, up to 80 cm recent snow overlies older interfaces comprising of surface hoar and sun crusts. The storm slab above these interfaces has the potential for wide propagations and surprisingly large avalanches.Wind slabs and new cornice development exist at ridgelines and on lee slopes. These are likely sensitive to human triggers. Cornices may become weak when the sun comes out on Friday.A strong melt-freeze crust exists at 1700 m and below and is bridging deeper instabilities. If temperatures warm this crust will likely break down causing the snowpack will weaken. The average treeline snow depths sit near 250 cm.
swerner,
Avalanche Canada
