Hatcher Pass
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The Bottom Line
The avalanche hazard is MODERATE for PERSISTENT SLABS at mid and upper elevations on WEST through EAST facing aspects on slopes 35° or steeper.
A LOW hazard exists on all other slopes and aspects for the same problem.
Last week’s storm included a few inches of graupel. Because of its size and water content, this snow can persist as a weak layer for some time (more in the problem discussion). In areas where this snow fell on a smooth firm crust, lingering instabilities still exist. Snowpit tests also point to the possibility of triggering an avalanche on a slightly deeper layer just below some of the wind slabs that formed during the previous week.
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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. |
Overall there were relatively few skiers out and around Hatcher Pass over the weekend, most making conservative terrain choices and sticking to mellow slopes. Despite this fact a couple parties observed some collapsing and a couple small skier triggered slides in the new snow. All this activity was reported in mid and upper elevation northerly facing terrain.
A small slide observed on the way to Farside on Tuesday. About 4k’ ft NW facing.
A few sunny days and warm temps helped initiate some wet loose activity on steep rocky solar aspects. If the sun comes out even briefly it has some strength. Avoid slopes that are becoming wet or unsupportable.
Last week’s snow has settled out and formed a soft but cohesive 6-10’’ slab in most locations. Skiing and riding is still generally soft and supportable on the north half of the compass. You’re not really feeling the bottom unless you’re on something steeper or where the recent storm snow was scoured away.
Skiers enjoying smooth turns on Nosebleed.
A few warm sunny days added a thin sun crust on solar aspects and have likely degraded riding conditions on these slopes.
A party enjoying good visibility in the eastern zone of the forecast area earlier this week.
| 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 |
Recent snow from Friday included 2-3’’ of graupel. Because of its size and water content this grain easily facets in cooler temperatures and can act as a weak layer for future avalanches. Additionally, this snow fell on a variety of surfaces including some areas of smooth firm crusts where it can act like ball bearings and increase instability.
Some graupel grains that have undergone metamorphism in both directions but are still showing some sharp edges (facets) on their perimeters.
Expect these avalanches to be 4-12’’ deep and 30-50’ wide and found on mostly northerly facing slopes west through east. While this problem should remain manageable for skiers, it will generally be found mid-slope in gullies, under cliffs, and where consequences of getting caught may be higher.
Recent skier triggered activity from Saturday below Microdot (see observation).
Snowpit tests also pointed to the possibility of triggering a slightly more deeply buried weak layer under the firm wind slabs that formed during periods of strong easterly winds 3/19 – 3/22. While this situation is less likely, the best course of action is still to follow safe travel protocols and only expose one person at a time if you’re skiing steep, exposed slopes on the north end of the compass.
Snowpack layering near the surface on upper elevation W/NW facing slope.
Lastly, while not a persistent slab issue, keep an eye out for warming temps and wet loose activity with daytime heating. We should see mostly cloudy skies the rest of this week but with mild temps and a weak refreeze overnight this could still be a possibility. Spring is trying to make a presence and when the sun pokes out, it has some strength to warm the snow quickly.
The strongest effect the weather has had on the snowpack over the last few days has been from the sun and mild temperatures. Winds remained light out of the S/SE but mild temps, high humidity, and some strong solar helped settle the recent snow and even dampened the snow surface on S facing slopes. Overall, the nice weather help settle and consolidate the snowpack in a positive direction, and on shady and sheltered slopes the skiing is still cold, soft, and supportable.
Mild temps through the weekend and some high humidity starting Tuesday helped settle and thicken the recent snow.
It’s currently snowing and an inch or two of snow is expected over the next few days with light to moderate southerly winds and mild temps in the 20’s. Visibility could be tough at times with high clouds and periods of snow showers.
Inspecting solar affect on the ridgeline with deteriorating visibility on the way.
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.
