Hatcher Pass
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The Bottom Line
The avalanche hazard is moderate for Glide Avalanches on all aspects at mid to upper elevation. Glide avalanches are not a human triggered hazard, but an unpredictable, naturally occurring event.
Glide avalanches are a low frequency/high consequence hazard. They are difficult to predict and can release at any time.
Avoidance is the best way to mitigate this hazard. Use your avalanche eye-balls and look around and above you. Identify glide cracks, “brown frowns”, and steer clear.
Glides that have already released are less likely to release a second time. However, it is possible for glide cracks to reform in these same places and produce repeat offenders. It’s just best to avoid any location with signs of glide activity.
More details on the glide avalanche problem at the bottom. of this page…
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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. |
Glide avalanches have been an ongoing issue at Hatcher Pass since the beginning of the season. Early snow fell on unfrozen, warm ground. This blanket of snow insulated the unfrozen ground. Unseasonably warm temperatures combined with the warm ground surfaces have allowed the snowpack to slowly glide down hill, eventually failing and releasing avalanches. The following pictures were taken on November 5. The glide avalanches pictured here have occurred over several weeks, some as recently as November 3, and some of the glide cracks are new.
Glide release on x4068 estimated to have occurred Wednesday, November 3 at 4pm. NE, 3100′
Hatch Peak, SE, 3000-4000′. Glides which have been forming and releasing for many weeks.
Marmot SE Bowls, 4000′, Glide crack
Marmot SE Bowls, 4000′, Glide avalanche
Marmot Mid-Rib, SW, 3500′. Glide cracks.
Glide avalanche release, Marmot, Death Gulley, SW, 3500′
Valle of Sin Glide Crack
Martin Mine Glide avalanche release this week, E, 4000′
Last weekends’ Halloween pineapple express puked record breaking water in the Southern Chugach but brought depressingly low snow amounts in the rain shadow at Hatcher Pass. Prior to the storm Hatcher Pass was enjoying stable avalanche conditions (other than glide avalanche issues) and good powder conditions in specific areas where early season coverage was good. However, strong winds through the Halloween storm popped that powder bubble, scouring ridges and stiffening up snow surfaces, producing drifting, sastrugi, and wind slabs. Wind slab instability was short lived.
The small amount of low density snow that fell after the main storm cycle left decent riding conditions in the mid to upper elevations in wind protected areas. If you find a window with good light this weekend, you will likely be able to sniff out soft powder conditions. There is a rain crust at the lower end of the mid elevation band that may ruin the quality of your powder experience, but if you get into the upper elevations this crust disappears.
Snow depth varies greatly. The lower elevations have little to no snow, and the mid to upper elevations have about 1 foot on the southern slopes and up to 3 feet on the northerlies.
The best news is our base, which is keeping us from hitting rocks. Don’t get me wrong, there are plenty of rocks showing and limiting our choices for riding. It’s still a bit early, not quite ripe, as most slopes need better coverage.
| 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 |
Glide avalanches are our only avalanche problem today. In areas where glide cracks and recent glide avalanche releases do not exist, avalanche stability is good. However the glide avalanche problem is constantly in flux, which means glides can appear anywhere, on any given day, anywhere where there is snow. Keep your eyes sharply peeled for this easy to identify hazard and avoid it.
Glide avalanche release is, well, let’s just say, impossible to predict. We can be fairly certain that glide releases will continue to occur this weekend and into next week, but as to what time of day…all bets are off.
Human triggering a glide avalanche is very unlikely. Glide avalanches are a naturally occurring event, and difficult to forecast. Glide avalanches can happen at any time of day or night and release does not necessarily correspond to weather events.
Glide avalanches fail at the ground, and this means that the entire snowpack slides down the mountain. Most glide avalanches are therefore sizeable and could easily result in injury, burial, or death. The hazard will be compounded where the runout of a glide avalanche funnels into terrain traps and shallow coverage will make rocks a major hazard for any avalanche.
The best method for dealing with this unpredictable hazard is to avoid it. Fortunately, this is relatively easy as glide cracks and recent glide releases are easy to identify.
For more information on this very interesting type of avalanche phenomenon around the Southern Chugach, click here for a great read. The Turnagain arm area, a generally maritime and warmer snowpack than Hatcher Pass, has had a long relationship with glide avalanches. Hatcher Pass historically has a more continental and colder snowpack. The first glide avalanches we’ve observed at HP occurred during the winter of 2018/19.
Looking forward, next week’s temperatures are forecasted to drop significantly and this may lead to some stabilization of the glide avalanche problem.
Reminders
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