Backcountry Avalanche Forecast for Southern San Juan 	
Issued: 02/16/2012 7:36 AM by Ethan Greene

Special Advisory Statement in Effect through 02/20/2012 10:00 AM

The Colorado Avalanche Information Center is issuing a Special Avalanche Statement for the mountains 
of Colorado this morning. This Special Statement will remain in effect through the upcoming weekend.
There have been two avalanche fatalities in Colorado since February 13th. This brings avalanche 
fatalities to 6 for the season. Over the last week seven people have been caught in avalanches. Two 
people have been seriously injured and required hospital care. Very large avalanches have been 
reported across the state. This trend is expected to continue through the holiday weekend.

Do not let the upcoming holiday weekend or the nice weather in any way fool you into thinking the 
avalanche conditions are anything but very serious across Colorado.

Highlights

Natural avalanche activity is decreasing, but human triggered avalanches are still likely. Small 
sluffs and soft wind slabs in the recent storm snow will be easy to trigger, and have the potential 
to trigger deeper and larger persistent slabs. Depending on the cloud cover, direct sun could 
trigger sluffs and possibly slabs this afternoon.

Avalanche Danger

The avalanche danger for the North San Juan is CONSIDERABLE (Level 3).

Snow & Avalanche Discussion

New snow totals are between one and a half to two feet since Sunday. Avalanche mitigation work on 
Wolf Creek Pass produced several soft-slab avalanches on near and below treeline slopes that face 
east and southeast. These slides were on to three feet deep. Yesterday a group of backcountry skiers 
triggered an avalanche on an east-facing, below-treeline slope near Wolf Creek Pass. They rolled 
several large pieces of cornice down a portion of the slope before triggering an avalanche that was 
about 2 feet deep and 80 feet wide. Although the snowpack is gaining strength, it is still possible 
to trigger avalanches on buried, faceted layers.

The western portion of the zone looks more like the snowpack in the Northern San Juan zone, which 
consists of the recent storm snow sitting on slabs in the middle and the upper portion of the 
snowpack interspersed with weak faceted layers. The whole stack of slabs is resting on very weak and 
well-developed depth hoar and basal facets.

The snowpack is generally stronger on the east side of the zone as you get closer to Wolf Creek Pass. 
Avalanches in the storm snow layer and below fresh wind slabs are the greatest concern in this area. 
There are multiple layers of buried surface hoar and near-surface facets in the top 3 to 5 feet of 
the snowpack, and a release in the storm snow could trigger one of these deeper persistent weak 
layers. You are most likely to find surface hoar on sheltered slopes that face northwest through 
north and to the east.

Weather Discussion for 11,000ft 	Issued: 02/16/2012 1:38 PM by Ethan Greene 	

A large low-pressure system, moving to the southeast though California, is pushing clouds and 
moisture into the Southern Mountains, while a weak short-wave trough clips the Northern Mountains. 
The combination will bring mild weather to most parts of the Colorado mountains. The sky cover 
decrease overnight. Winds will remain light to moderate in all area except the northern portion 
of the Front Range zone. Temperatures will be slightly cooler than last night. Friday will begin 
with mild weather, but another weak short-wave trough will move into the state from the north late 
in the day.