Hatcher Pass
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The Bottom Line
The snowpack is slowly gaining stability.
Small to large human-triggered persistent slab avalanches 1-3′ deep are possible in specific locations on Southwest thru Northeast aspects at upper and mid-elevations. Natural avalanches are unlikely. The avalanche danger is low below 2500′.
Triggering an avalanche of any size could have severe consequences due to shallow coverage and rocks.
There is good snow that can be found in the forecast area. However, riding in terrain traps is not worth the risk. Don’t be fooled by what others get away with.
Starting Thursday evening, the forecast area is expected to receive 3 to 5” of new snow. This new snow could tip the balance and cause avalanche danger to rise. Be on the lookout for shooting cracks and collapsing(whumping).
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| Travel Advice | Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. | Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern. | Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding, and conservative decision-making essential. | Very dangerous avalanche conditions. Travel in avalanche terrain not recommended. | Extraordinarily dangerous avalanche conditions. Avoid all avalanche terrain. |
| Likelihood of Avalanches | Natural and human-triggered avalanches unlikely. | Natural avalanches unlikely; human-triggered avalanches possible. | Natural avalanches possible; human-triggered avalanches likely. | Natural avalanches likely; human-triggered avalanches very likely. | Natural and human-triggered avalanches certain. |
| Avalanche Size and Distribution | Small avalanches in isolated areas or extreme terrain. | Small avalanches in specific areas; or large avalanches in isolated areas. | Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas. | Large avalanches in many areas; or very large avalanches in specific areas. | Very large avalanches in many areas. |
The last human triggered avalanche was Nov 19th. No natural avalanches have been observed over the last week.
| Signal Word | Size (D scale) | Simple Descriptor |
| Small | 1 | Unlikely to bury a person |
| Large | 2 | Can bury a person |
| Very Large | 3 | Can destroy a house |
| Historic | 4 & 5 | Can destroy part or all of a village |
Small to large human-triggered avalanches 1-3’ deep are possible on Southwest thru Northeast aspects at upper and mid-elevations, or any area with signs of previous wind loading. Expect deeper and larger avalanches in areas with a thicker snowpack. Remotely triggering an avalanche is possible. These avalanches could be 60 to 100′ wide.
The snowpack has had time to adjust to the snowfall that occurred on 11/13-14. Unseasonably warm temps over the last week have allowed for flaws within the snowpack structure to start healing. Weak sugary faceted snow can still be found at or near the ground. If you find an area with a stiff cohesive slab sitting on weak sugary snow, proceed with caution. This is easy to identify with pole tests.
Skyscraper and Eldorado Bowl are good examples of areas with previous wind loading.
To visually identify areas with previous wind loading look for signs for smooth wind-drifted snow. Pole probes, hand pits, and other traveling tests will help you identify the persistent slab problem. Cracking and collapsing will be red flags for this avalanche problem. Formal stability tests will also help you identify poor structure and poor stability.
We recommend staying disciplined with your safe travel protocols when on or near avalanche terrain. Tracks on a slope are not a sign of stability.
Many areas have thin shallow snowpack. Rocks, shrubs and other hazards are waiting just below or at the surface.
There is good snow that can be found in the forecast area. However, riding in large terrain traps is not worth the risk. Don’t be fooled by what others get away with.
Be sure to check out the avalanche forecasts from last week. This season’s archived forecasts have important details on the evolving persistent slab problem.
