|Fri, December 29th, 2023
|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.
No new avalanches were observed since Saturday 12/23. With good visibility we were able to photograph the evidence of older avalanches.
12/26 Marmot mid rib human triggered avalanche from 12/23 SW 4400′
12/26 Old crown on NE Frostbite, likely from 12/22
12/26 Catchers mitt avalanche from 12/23
12/26 Lower Eldorado debris, likely from 12/23
Dry weather and light winds have allowed the snowpack to stabilize, making it unlikely to trigger an avalanche. Unless you are descending a wind hardened surface or a scoured ridgeline, good skiing can be found on most aspects and elevations in Hatcher Pass. No recent avalanches have been reported since Saturday 12/23. Some isolated locations may still hold the right ingredients for a slab avalanche.
Ridgelines in the mid and upper elevations saw a fair amount of wind action this past weekend, with a 20 hour window of strong winds from the southeast gusting to 48 mph on Saturday morning. The low density snow was transported from windward aspects and rapidly deposited to leeward slopes. This contributed to firm snow surfaces on south to east aspects while loading west to north aspects. As a result, three human triggered avalanches failed at the new snow/old snow interface with slabs around 6 to 10 inches thick. Over time this activity has subsided and wind firmed slabs have been acting stubborn.
Cornices have also grown in size as the transported snow eddies and collects on leeward ridgelines. The build-up of consolidated snow can become very large and over-hanging to the point where they break when stood upon or collapse naturally.
In terrain steeper than 40 degrees you could trigger a small dry loose avalanche. These will be manageable sluffs that entrain the unconsolidated surface snow. You could find this type of avalanche problem in isolated locations or extreme terrain on all aspects and elevations.
We are still finding weak sugary grains in isolated locations of the snowpack. While we have not seen a persistent slab avalanche since 12/20, do not rule out these weak lingering layers. Look for hard snow sitting over weak and unconsolidated snow. Evaluate the snowpack in multiple locations, perform pole probes, hand shears and instability tests to give you some information on the potential for propagating one of these avalanches.