Chugach State Park

Fri, December 1st, 2023 - 7:00AM
Sat, December 2nd, 2023 - 7:00AM
Mary Gianotti
Conditions Summary

Weekend Avalanche Outlook

Saturday, Dec. 2 to Sunday, Dec. 3

Bottom Line: There are two main avalanche problems we are most concerned with in the Chugach State Park this weekend. The first is wind slab avalanches between 6″ to 2 feet deep. These can be found predominantly on north and west aspects along with other wind loaded terrain features. The second problem is triggering a larger slab avalanche that breaks in weak snow at the middle or base of the snowpack. This last issue has only been seen at higher elevations in alpine start zones.

Special Announcements

Welcome to the Chugach State Park conditions page. We are in the process of ramping up a weekend avalanche report for Anchorage’s Front Range. Our goal is to provide avalanche information for high use areas of the Chugach State Park in an effort to assist recreationalists in making informed and safe backcountry travel decisions.

Areas include the Anchorage Front Range (i.e., Flattop/Glen Alps) and the South Fork of Eagle River. The outlook’s primary audience will be winter hikers, backcountry skiers/snowboarders, snowmachiners, snowshoers, fat bikers, and climbers.

Recent Avalanches

Over the past two weeks, we know of one significant human triggered avalanche. This was a wind slab that was triggered by a skier on Flattop on November 22nd. The avalanche was reported at 18” deep and 70’ wide. It was triggered on a west aspect on a 32 degree slope at roughly 3,200 feet in elevation while the skier was skinning up to their objective.  The skier was caught but not buried and is OK. Otherwise, on our field day on November 28th  we were able to trigger a handful of small wind slabs on small terrain features.

Weather Recap: The Front Range did not receive a drastic amount of fresh snow from the Nov 29-30 storm unlike our neighboring snowpack down at Turnagain Pass. In fact, only a few inches of snow has fallen since the Thanksgiving rainstorm. However, over the past week, the Front Range did experience sustained moderate to strong winds predominantly from the SSE.

Looking ahead at the weather forecast for this weekend, models are predicting mostly sunny skies with light winds from the NE. Temperatures should range from 15-25F.

Snow depths range greatly in the Front Range at the moment, from bare ground (mostly on SE aspects) to over 8 feet in wind deposited locations. Because of the early season snowpack and strong winds during November, immense spatial variability exists.

Avalanche Problem 1
  • Wind Slabs
    Wind Slabs
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
More info at

Because there are no drastic events predicted in the weather forecast this weekend, our avalanche problems should remain similar through the weekend.

Wind slabs have been observed at multiple locations throughout the Chugach State Park. These have mostly been seen on the north and west aspects. Wind slabs could be anywhere from a foot deep to 3 feet deep or more in places that have seen significant wind loading. The classic wind slab signs to look for are shooting cracks and stiffer snow that often sits on softer snow.

Shooting cracks on a small rollover terrain feature near Blueberry Hill near the Glen Alps Recreation Area. 11.27.23.


Skier triggered wind slab on small test slope at Glen Alps Recreational Area. 11.27.23

Avalanche Problem 2
  • Persistent Slabs
    Persistent Slabs
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
More info at

There are two weak layers we have found in the snowpack at the higher elevation alpine start zones that are just as concerning as the wind slabs mentioned above. One is a facet/crust combination that sits around 15″ below the surface and the other is a layer of facets at the base of the snowpack. We don’t know of any avalanches that have released in these layers yet but this is a concerning setup. They have been seen in the South Fork of Eagle River, Arctic Valley, and Peak 3 and most pronounced at elevations over ~2,700ft. The common red flags for an unstable snowpack are listening for “whumphing” sounds and the feel and sound of the snowpack collapsing beneath you along with cracks in the snow that shoot out from you. If any of these signs are present then the slope can avalanche if it’s steep enough.


Snowpit at Peak 3 on Thursday, November 30th


Snowpit at Glen Alps Recreational Area on November 28th

Fri, December 1st, 2023

Weather Forecasts:

Weather Stations

Recent Observations for Chugach State Park
Date Region Location
05/29/24 Chugach State Park Avalanche: Harp mtn west aspect
05/07/24 Chugach State Park Observation: Mt. Eklutna
04/27/24 Chugach State Park Avalanche: Chugach Front Range Powerline Valley
04/16/24 Chugach State Park Observation: South Fork of Eagle River
04/13/24 Chugach State Park Avalanche: South Fork Hiland Road
04/10/24 Chugach State Park Observation: Chugach Front Range Flattop
04/09/24 Chugach State Park Observation: South Fork of Eagle River
04/08/24 Chugach State Park Avalanche: Arctic Valley/ Gordon Lyon
04/06/24 Chugach State Park Observation: Eagle River South Fork
04/06/24 Chugach State Park Avalanche: False Peak

This is a general backcountry conditions summary. This advisory does not apply to highways, railroads or operating ski areas.