Avalanche Forecast
Issued: Apr 7th, 2013 9:25AM
The alpine rating is Wind Slabs, Cornices and Loose Wet.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Due to limited field observations
Weather Forecast
Synopsis: The Cascades could see another 10-15 cm by Monday morning. A brief ridge of high pressure will result in drier conditions and sunny breaks on Monday. The next system arrives sometime on Tuesday bringing moderate precipitation through Wednesday. Monday: Cloudy with sunny breaks. The daytime freezing level rises to around 1500 m. Winds are light from the northwest. Tuesday: Increasing cloud with precipitation developing in the afternoon (~10-15 cm). The freezing level is around 1300-1500 m. Winds increase to moderate or strong from the southwest. Wednesday: Moderate precipitation continues. The freezing level is steady between 1300 and 1500 m.
Avalanche Summary
There are no new reports of avalanches from the region. Watch for an increase in solar related avalanche activity on Monday (loose wet, cornice) and the potential for triggering fresh wind slabs in lee alpine terrain.
Snowpack Summary
Recent snowfall amounts vary depending on location and elevation. Some alpine areas (above 1800-1900 m) could have accumulations of over 40 cm from the past couple days. New dense wind slabs are likely in exposed lee and cross-loaded terrain in the alpine. Most of the recent precipitation has fallen as rain below treeline. Rain had turned to snow down to 1000 m on Sunday morning leaving 10-20 cm of moist snow bonding well to wet grains below. Below the dusting of new snow the upper snowpack at lower elevations has become isothermal from recent warm temperatures and rain. Cornices are very large and could pop off with continued mild temperatures.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Loose Wet
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 8th, 2013 2:00PM