Avalanche Forecast
Issued: Dec 19th, 2013 7:56AM
The alpine rating is Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair
Weather Forecast
Friday: Cloudy with light to moderate snowfall around 5 cm. The freezing level is at valley bottom and ridgetop winds are light to moderate from the northwest. Saturday: Mainly cloudy with a chance of flurries and sunny breaks. The freezing level remains at valley bottom and moderate gusty northwest winds continue. Sunday: A mix of sun and cloud. The freezing level is near valley bottom and the upper flow continues to be northwesterly.
Avalanche Summary
One size 3 accidentally triggered slab avalanche was reported near Golden on Wednesday. This slide was triggered by a skier on a north-northeast aspect in the alpine and likely released on a persistent weakness near the bottom of the snowpack. The initial slide also sympathetically triggered another size 2.5 lower down the slope. Fortunately no one was buried or injured. Several other natural and explosive triggered avalanches (size 1.5-2.5) were reported - most were from the northern part of the region where up to 20 cm of new snow fell in the previous 24 hours. This type of avalanche activity may be a good indication of the potential for large avalanches during periods of loading.
Snowpack Summary
Up to 20 cm of low density new snow fell with the latest system, accompanied by moderate W-NW ridgetop winds. Expect to find dense wind slabs in exposed lee terrain at and above treeline. A couple notable persistent weak layers can be found in the top 60 cm. These layers have produced variable results with snowpack tests, but are increasingly concerning as the load above increases and/or a slab develops. If you're in the Golden area check out the latest update on local conditions from Skiing Golden. At the base of the snowpack are weak facets and depth hoar combined with a crust from early October. This deep persistent weakness may be stubborn to trigger, especially in deeper snowpack areas, but the sensitivity to triggers likely increases in shallower locations, especially on steep, convex, north-facing slopes. Snow depth is still below threshold in many areas below treeline.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 20th, 2013 2:00PM