Hatcher Pass
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The Bottom Line
The avalanche danger is MODERATE for PERSISTENT SLABS at all elevations.
Another winter storm will bring an additional 8-12″ of new snow to Hatcher Pass Thursday through Friday. Expect small STORM SLABS to be possible to human trigger above 2500′ in the afternoon as storm totals start to accumulate.
The return to winter combined with a new avalanche problem is a great reason to maintain safe travel protocols to increase your margin of safety.
| Fri, April 5th, 2024 |
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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. |
Hatcher Pass experienced an exciting and dynamic shift this week with the 3/30-31 Easter Bunny Storm that brought up to 23″ of new snow with 1.8″ SWE combined with winds ESE>SE 27 gusting 31-47mph for 9 hrs on Marmot at 4500′ and ESE>SE 32-41 gusting 40-62mph for 16hrs on Hatch at 4561′. Several natural D1-D2 (small to large) storm slabs and wind slabs were observed and reported, mostly above 3000′. Two remotely triggered avalanches were reported on Monday on the Sunnyside of Hatch and Skyscraper. A third remotely triggered slab avalanche occurred on Bennet’s ridge on Tuesday. This avalanche appeared to have sympathetically triggered an adjacent avalanche.
Another pulse of precipitation is forecasted to bring 8-12″ of new snow Thursday afternoon through Friday above 2500′.
4/3 Human triggered D1 slab avalanche on Peak 4068′ NNW 3600′
4/1 Human triggered storm slab on Sunnyside of Hatch that occurred early morning, SSE 4000′ SS-ARu-D2-I
4/1 Same photo as above, different angle
4/1 Human triggered dry loose sluffs that gained momentum with older faceted snow , Eldorado Bowl>Liams Run NE 4200′
4/1 Natural wind slab on main gut of Marmot, left of mid-rid and right of Lodge run, WSW 4400′
| 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 6-20″ thick will be possible to human trigger on all aspects, at all elevations, on slopes 30º and steeper. Natural avalanches are unlikely. Expect slabs to be thinner at low elevation and on southerly aspects, and thicker at upper elevation and northerly aspects.
Over the past few days, three remotely triggered slab avalanches have occurred on east, southeast, and northeast aspects above 3500′. Finding possible locations to trigger a slab will be challenging and will require finding buried weak sugary snow (NSF) sitting on top of firm bed surfaces (wind or melt freeze crusts). This combination of weak layer and bed surface is not widespread and does not exist everywhere. Shallow spots in the snowpack will be more likely locations to trigger a slab. Remotely triggering an avalanche will be possible due to the continuity of the weak layer that exists in specific locations.
The persistent slab avalanche (photo below) likely occurred on April 2 on Bennet’s Ridge. 
4/2 Remotely triggered slab avalanche on Bennet’s Ridge that sympathetically triggered another avalanche NE 3900′
TRAVEL RECOMENDATIONS :
It’s springtime and easy to become complacent especially with the lack of avalanche problems we have seen this season. Good rules of thumb no matter the avalanche danger include: only expose one person to steep slopes at a time, choose safe zones out of the reach of avalanches for grouping up, always have a spotter in a safe location, everyone carries a beacon, shovel, and probe, and are prepared and practiced for companion rescue.
Lastly, there’s some nice powder out there to recreate in. If you get out and about, send us your avalanche, snow and weather observations HERE. We love your pictures. You can also share by DM’ing us on Facebook @hpavalanche and Instagram @h_p_a_c
| 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 |
Another winter storm will intensify this afternoon bringing 8-12″ of new snow with up to 1″ SWE to Hatcher Pass Thursday afternoon through Friday. Expect 4-6″ of new snow by end of the day to build small STORM SLABS that will be possible to human trigger on all aspects above 2500′. Some uncertainty still exists with storm totals. Expect storm slabs to fail on weak sugary facets or graupel sitting on firm crusts.
To identify this avalanche problem use formal stability tests and hand pits to see if the new snow is behaving like a slab. Shooting cracks and whumping will be a red flag for this avalanche problem. Storm slabs are typically reactive for a few hours to a couple days.
