Hatcher Pass

Numerous Glide Avalanches have been releasing, with the most recent report from November 2. See video below.

Check out the numerous observations on the Observations page for more information and pictures of various, recent Glide Avalanches. If you are out and about Hatcher Pass, please submit your observations with the community and the avalanche center. If posting to social media, add the #hpavy to make it easy to find Hatcher Pass snow related information.

Multiple, old Glide Avalanches on the lower roll of Eldorado, E, 3600′

Glide avalanche on Willow side of Hatcher Pass proper.

Rain/drizzle crust with stress cracks. We have encountered this crust up to 5000′. The crust is 0.5-3cm depending on the area and elevation, is fairly easy to ski through, with a lot of powder locked under the vault of the crust.

Glide avalanches occur when the entire snowpack slowly slides as a unit on the ground. Glide avalanches can be composed of wet, moist or almost entirely dry snow and pose a hazard that is very difficult to forecast and predict. They are often preceded by glide cracks (full depth cracks in the snowpack), though the time between the appearance of a crack and an avalanche can very between second and months.

As a general rule, avoid being under or on any location where glide cracks are present, and glide avalanches are present. Some portions of glide avalanches that have already occurred, actually still have portions that have not yet released and therefore still pose a threat. Glide avalanches may run farther than you think, and may run down a slope and overrun flat terrain. Ensure you are not in the runnout of a possible glide avalanche. These cracks are fairly easy to identify, with a large upside down frown of a crack, resembling a crevasse, sometimes showing the dark ground surface. Review the pictures on the observation page for great examples of what to look for.

You will notice a pattern to the location of Glide Avalanches. They tend to be occurring on steep slopes, 35º and steeper, on slopes with smooth ground surfaces, such as grass or rock slabs, and the majority reside near an old rain line of approximately 4000´, with some as high as 4500′.

The current snowpack structure is entirely composed of rounded grains, melt freeze crusts, and ice lenses. Basically, there’s not a single facet in there, which is extremely rare! We currently have 2-3+ feet of snow as a base. Most of this seasons precipitation has fallen during periods of warm temperatures, sometimes as rain. A wet to moist snowpack, warm temps, and early (and now deep) snow insulating a warm ground surface are all contributing to the Glide Avalanche problem. This problem is not likely to go away soon.

The good news is, that where Glide Avalanches are not occurring or forming, the stability is quite good. We are still in the ealry stages of developing a thorough understanding of the snowpack, but testing has been fairly consistent, and each snowstorm has bonded well to older snow surfaces.

There is a structural flaw at the base of the snowpack, where weaker snow is sitting under stronger snow, and this is the layer that is creeping and failing in the Glide Avalanches. Its important to recognize that Hatcher Pass has seen a lot of backcountry traveler activity without human triggered avalanche results. Add that to good overall structure in the snowpack, a lack of typical weak layers, and a lack of propagation results and we are trending towards forecasting good stability in areas that lack glide cracks and glide avalanches.