Hatcher Pass
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The Bottom Line
The avalanche danger is MODERATE for PERSISTENT SLABS at all elevations and on slopes 35º and steeper.
It will be possible to trigger an avalanche on steep southerly aspects ( southeast to southwest) up to 12 inches thick AND less likely but still possible on northerly aspects (northwest to northeast) at upper elevation up to 3 feet deep.
Natural avalanches are unlikely.
Cornices are huge and serious hazard on upper elevation leeward aspects. Don’t trust them! Give them a wide birth and stay back!
Don’t roll the dice today. Choose your aspect and slope angle wisely. Keep it mellow and stay off steep southerly.
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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. |
Several human triggered slab avalanches occurred on Friday on southerly aspects including one remotely triggered avalanche. We also observed naturals likely from Wednesday’s new snow and wind that we did not see on Wednesday due to poor visibility.
Check out the observations page for more detailed info on recent avalanches.
3.3 Before the avalanche
3.3 Human triggered persistent slab SE 4200′ Upper eldorado bowl. Triggered while skinning uphill.
3.3 Same avalanche as above
3.3 The same party who triggered an avalanche in Eldorado (pictures above) triggered these two slabs which sympathetically triggered a third avalanche. S Skyscraper 3500-4000′
3.3 Remotely triggered slab avalanche on Vice Presidents, Marmot, SSE 3200′
3.3 Human triggered avalanche up Archangel/Reed Lakes area, SSW aspect 4100′
3.2 Human triggered slab avalanche on Marmot mid-rib that funneled into the Death gully, S Aspect, 3500′
3.2 Same avalanche as above showing the crown and smooth bed surface in this photo
3.2? Natural slab avalanche on the Punk Spines WNW 3500′. This avalanche likely occurred on 3.1.
3.1 Impressive natural avalanches on SE to SW aspects on Idaho Peak 3000-4000′. We believe these went naturally on Wednesday 3/1. Scroll in to see all the crowns.
3.1 Marmot S 4500′ Natural or remote trigger from the lodge run? Scroll in to see the crown just below the cornice which appears several feet thick.
| 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 |
Persistent slabs will be possible to human trigger in specific locations. The most likely location to trigger a slab this weekend will be steep southerly aspects above 3500′. It will also be possible to remotely trigger an avalanche on southerly aspects due to the continuity of the weak layer and smooth bed surface. Natural avalanches are unlikely.
Six human triggered avalanches were reported on Friday on steep southerly aspects while few people were recreating in the backcountry. Expect these avalanches to be up to 12″ deep. While most have been small, some are definitely capable of burying or injuring.
The easiest way to avoid triggering an avalanche this weekend is to carry a compass like the most seasoned forecasters or a compass on your watch if you are born in the 90’s and avoid steep southerly aspects. It takes familiarity with terrain and constant assessment of how a slope can slightly change aspect on an ascent or descent to avoid problematic locations. Expect the human factor to be high with today’s sunshine and Wednesday’s fresh coat of snow which may try to lure you to sunny southerlies.
This avalanche was triggered yesterday while skinning uphill on a southerly aspect in Eldorado Bowl. Fortunately, no one got caught and the runnout was gentle.
Cold temperatures this week have contributed to the faceting process in the snowpack, specifically on buried crusts, which makes todays problem more likely to trigger than last week. If you feel a firm buried suncrust while performing pole tests and hand shears, combined with terrain 35º and steeper, on a southerly aspect (southeast to southwest), the probability is significantly higher that you will trigger an avalanche.
This avalanche was triggered on Thursday on a S aspect of the Marmot midrib. Although small, the consequences are big because of the terrain trap (aka death gully) that it funneled into. More info here.
In isolated and extreme terrain it will be possible to trigger a persistent slab up to 3 feet deep on northwest to northeast aspects at upper elevation. After the loading event on Wednesday with 6″ of new snow combined with strong wind for 12+ hours, we observed several small to large naturals on leeward aspects on Government and Arkose Ridge. The most problematic terrain will be in areas with a thinner snowpack with old smooth, firm buried faceted wind slabs combined with paths that have previously avalanched this winter. We also expect to see more naturals in this terrain with the next loading event.
Whumping and shooting cracks will be red flags for this avalanche problem.
If you head into avalanche terrain today, utilize strict safety travel protocols, travel one at a time from safe zone to safe zone, only have one person on slope at a time, ensure all members of your party are carrying and know how to use beacons, shovels and probes, and avoid slopes with terrain traps.
| 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 |
It will be possible to trigger a small to large loose dry avalanche (sluff) in steep terrain 40º and steeper, in protected locations, especially where a smooth crust bed surface exists.
Cold clear weather this weekend will continue to facet out snow surfaces, increasing the size and potential for triggering a sluff.
Loose dry sluffs are manageable and avoidable.
After numerous storms and several wind events, we have reached that time of the year when cornices are large and unpredictable. Unfortunately, many slopes we want to ascend, ski, and ride, also have cornices at the top. Use your partners to help spot you and give advice on how overhung cornices are. It can be challenging to assess how overhung these huge monsters can be. Give cornices a large conservative berth when traveling around them as well as staying aware of who might be below you.
Large, overhung cornice on Marmot overhanging Rae Wallace. This person unintentionally broke a large cornice off and did not realize how close he was to the edge.
