Hatcher Pass Avalanche Center

Hatcher Pass RSS

ARCHIVED - Forecasts expire after 24 hours.
Sat, February 18th, 2023 - 7:00AM
Sun, February 19th, 2023 - 7:00AM
Allie Barker
Avalanche risk The Bottom Line

The avalanche danger is MODERATE at all elevations.

Small to large loose dry avalanches will be likely to human trigger on steep slopes with 16″+ of low density snow that has fallen since Feb 11th.

Natural avalanches are unlikely.

Overcast skies will linger and bring an additional 3 to 4″ of new snow expected by the end of day today.

Special Announcements

HPAC has funded scholarships for six local residents seeking avalanche training this season! We have funding available for two more individuals – if you’re a Mat-Su Valley resident who is enrolled on a recreational avalanche course this season, visit our Scholarships page to apply for financial assistance.

Sat, February 18th, 2023
Upper Elevation
Above 3,500'
2 - Moderate
Avalanche risk
Mid Elevation
2 - Moderate
Avalanche risk
Low Elevation
Below 2,500'
2 - Moderate
Avalanche risk
0 - No Rating
1 - Low
2 - Moderate
3 - Considerable
4 - High
5 - Extreme
Avalanche risk Avalanche risk Avalanche risk Avalanche risk Avalanche risk
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.
Recent Avalanches

No new avalanches have been observed since the human triggered near miss on Feb 15th. See observation HERE from yesterdays avalanche assessment on Marmot.

Numerous small natural wind slabs occurred mid-storm on Feb 14th when ESE winds gusted 20-31mph for 12 hours. These wind slabs failed just below ridgelines on SW to N aspects at upper elevation. One outlier was a larger slab avalanche on the NNW aspect on the Punk Spines at 3700′ in a zone we believe avalanched earlier in the season. For more info and pics of these avalanches see Thursdays forecast HERE.

Above: 2/14 Natural, loose dry avalanches (sluffs)on east aspect of Skyscraper 3800′


Above: 2/14 Natural, slab avalanche on Punk Spines NNW aspect 3700′. Debris ran almost all the way to the main drainage.


Above: Punk Spines, same avalanche as picture above


Avalanche Problem 1
  • Dry Loose
    Dry Loose
  • Certain
    Very Likely
  • Historic (D4-5)
    Very Large (D3)
    Large (D2)
    Small (D1)
Dry Loose
Dry Loose avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.

Likelihood of Avalanches
Terms such as "unlikely", "likely", and "certain" are used to define the scale, with the chance of triggering or observing avalanches increasing as we move up the scale. For our purposes, "Unlikely" means that few avalanches could be triggered in avalanche terrain and natural avalanches are not expected. "Certain" means that humans will be able to trigger avalanches on many slopes, and natural avalanches are expected.

Size of Avalanches
Avalanche size is defined by the largest potential avalanche, or expected range of sizes related to the problem in question. Assigned size is a qualitative estimate based on the destructive classification system and requires specialists to estimate the harm avalanches may cause to hypothetical objects located in the avalanche track (AAA 2016, CAA 2014). Under this schema, "Small" avalanches are not large enough to bury humans and are relatively harmless unless they carry people over cliffs or through trees or rocks. Moving up the scale, avalanches become "Large" enough to bury, injure, or kill people. "Very Large" avalanches may bury or destroy vehicles or houses, and "Historic" avalanches are massive events capable of altering the landscape.

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
More info at Avalanche.org

Loose dry avalanches (sluffs) will be likely to human trigger at all elevations, on all aspects, in protected terrain steeper than 40º.

With an additional 3 to 4″ of new snow in the past 24 hours, combined with 12″ of new snow from 2/11-2/13 the likelihood for triggering a sluff continues to carry the potential to injure or bury a person especially if compounded by the risk of a terrain trap. An additional 3 to 4″ of new snow expected over the next 24 hours will add to this avalanche problem.

Look for and pay attention to buried crusts up to 2 ft deep that will act as a smooth bed surface for sluffs to gain momentum. We have more recently found buried crusts in shallow isolated locations on southerly aspects.

Earlier in the week, we observed and received reports of people triggering and getting caught in small to large sluffs in steep terrain.

Getting caught in a loose dry avalanche in steep terrain may sweep you into terrain traps compounding the overall hazard.  We mention this often because a significant amount of the terrain at Hatcher Pass involves navigating in, around, or above terrain traps.

We recommend avoiding terrain traps, skiing/riding one at a time, using appropriate safe zones, and using appropriate sluff management techniques.

Lastly, just because Loose Dry is the main concern of the day doesnt mean it is impossible to trigger a slab avalanche. As seen with the near miss on Wednesday, we can dig pits and gather data yet still miss a few pieces to the puzzle.  Terrain features can make it challenging to recognize cross-loaded features and slopes that previously avalanched during the season will have a different structure.  Few people have found evidence of buried persistent grains in the past few weeks, although it does exist in isolated and extreme terrain.  We always encourage investigation of the snowpack, no matter the danger.

Additional Concern

Wind Slab

The winds had a mild and brief presence yesterday gusting SSE 15-19mph for 6 hours at 4500′. During our tour we observed 1-2″ thick wind slabs forming at 4000′ around 1pm.  Expect these wind slabs to be 2″ thick, on W to N aspects, at upper elevation, and located at or just below ridgeline. These soft wind slabs will be easily manageable but also will become buried by an additional 3-4″ of new snow expected by end of day today.


Sat, February 18th, 2023

On 2/17 winds from the SE gusted 16-19 mph for 6 hours at 4500′.

IM at 3550′ reported 3-4″ of new snow in the last 24 hours.

Frostbite at 2700′ reported 3″ of new snow in the past 24 hours.


NWS AVG Forecast here.

NWS point forecast here.

Marmot Weather Station here.

Independence Mine Snotel here.

Frostbite Bottom Snotel here.

State Parks Snow Report and Motorized Access information here.

XC trail grooming report for Mat-Su, Anchorage, and Kenai here.

Recent Observations for Hatcher Pass