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Avalanche Forecast

Apr 2nd, 2018–Apr 3rd, 2018
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: Northwest Inland.

New snow and wind may form reactive storm slabs on Tuesday. Watch for signs of increasing danger such as cracking, whumpfing, or avalanche activity.

Confidence

Moderate - Forecast snowfall amounts are uncertain on Tuesday

Weather Forecast

TUESDAY: Scattered flurries with 5-15 cm of new snow, moderate south wind, alpine high temperatures near -10 C, freezing level up to 400 m.WEDNESDAY: Mostly cloudy and light snowfall with accumulations of 1-3 cm, light south wind, alpine high temperatures near -9 C, freezing level up to 500 m.THURSDAY: Light flurries with trace accumulations, light to moderate south wind, alpine high temperatures near -10 C, freezing level up to 400 m.

Avalanche Summary

Avalanche activity on Sunday was limited to a few small loose avalanches on steep sun-exposed slopes.On Saturday, a large persistent slab avalanche was reported in the north of the region, failing on the early-March weak layer. It failed on an easterly aspect around treeline. Portions of the avalanche stepped down to sugary facets near the bottom of the snowpack.Otherwise, there was further evidence of a large natural cycle that occurred on Friday within the recent storm snow, with storm slab and loose dry avalanches. They were small to large (size 1 to 2.5), on all aspects and elevations.

Snowpack Summary

5-15 cm of new snow is expected on Tuesday. The new snow will sit above a sun crust on southerly aspects from the weekend's clear skies.A reactive slab about 50 cm thick has developed after last week's storm. On shaded aspects at high elevations, this slab overlies two layers of weak surface hoar. On all aspects below treeline, the slab sits on a melt-freeze crust. The storm snow may still be loose in sheltered and shady locations.Near the bottom of the snowpack, weak and sugary facets are found in shallow, rocky snowpack areas. Storm slabs have stepped down to these facets recently, producing very large avalanches.

Avalanche Problems

Storm Slabs

Some areas may get enough snow to form fresh slabs, especially on wind-loaded slopes. Older storm slabs from last week are still a concern as the snow is not bonding well to layers of surface hoar, crusts, or sugary facets.
Use caution above cliffs and terrain traps where small avalanches may have severe consequences.Minimize exposure during periods of heavy loading from new snow and wind.Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 2.5