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Avalanche Forecast - South Rockies   

Date Issued   Friday, 03 February 2012 6:34 PM      Valid Until    Saturday, 04 February 2012 11:00 AM

This is the first significant warm spell of the season and the snowpack is revealing its secrets, especially in alpine locations. Make conservative terrain choices as destructive avalanches are a real possibility.

Danger Rating: Saturday Alpine Treeline Below Treeline
3 - Considerable Dangerous avalanche conditions. Careful snowpack evaluation, cautious route finding and conservative decision making essential.
3 - Considerable Dangerous avalanche conditions. Careful snowpack evaluation, cautious route finding and conservative decision making essential.
2 - Moderate Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Sunday Monday
Alpine 3 - Considerable 3 - Considerable
Treeline 3 - Considerable 2 - Moderate
Below Treeline 2 - Moderate 1 - Low
Confidence: Fair - Freezing levels are uncertain
Learn more about danger ratings
Low Moderate Considerable High Extreme

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Natural and human-triggered avalanches unlikely.

Small avalanches in isolated areas or extreme terrain.

Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

Natural avalanches unlikely; human-triggered avalanches possible.

Small avalanches in specific areas; or large avalanches in isolated areas.

Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

Natural avalanches possible; human-triggered avalanches likely.

Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas.

Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.

Natural avalanches likely; human-triggered avalanches very likely.

Large avalanches in many areas; or very large avalanches in specific areas.

Avoid all avalanche terrain.

Natural and human-triggered avalanches certain.

Large to very large avalanches in many areas.
Cornices
What Elevation Zone?
Which Slopes?
Chance of Avalanches?
Expected Size?
Cornices are large, unsupported and tender right now. Give cornices a wide berth from above and below. They usually require more space then initially anticipated. With current warming, cornices will become weak.
Deep Persistent Slabs
What Elevation Zone?
Which Slopes?
Chance of Avalanches?
Expected Size?
Deep persistent slabs may be triggered with a larger trigger (cornice, sled). They may also be triggered by solar warming
Wind Slabs
What Elevation Zone?
Which Slopes?
Chance of Avalanches?
Expected Size?
Strong SW winds have formed wind slabs on lee slopes and below ridgecrests.
Travel and Terrain Advice
  • Extra caution needed around cornices with current conditions.
  • Be aware of the potential for full depth avalanches due to deeply buried weak layers.
  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

Prepared by jlammers