|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.
No natural or human-triggered avalanches have been observed since December 23rd.
2 inches of new snow has made a slight improvement in riding conditions.
Hatcher Pass was wind hammered for Christmas (Dec 23-26) and firm conditions are widespread. 2″ of new snow at IM Snotel in the last 7 days has made for some small improvement along with some slow faceting/softening of the previous snow surface. We have been finding very isolated locations of soft snow, with mostly a mix of breakable and supportable crusts and wind-packed firm snow.
As seen in almost every observation this season, poor structure exists in the snowpack. This means that we have strong snow overlying weaker snow. This paradigm is troublesome, and each time we have seen a rapid load, such as a big dump of snow, or strong wind loading, our snowpack has been overloaded and avalanche activity was the result. The last avalanche cycle was recorded on December 23rd when winds spiked rapidly overloading the snowpack and resulting in numerous large natural avalanches. After this event the spike of avalanche activity subsided and the snowpack adjusted and stability increased despite the structural flaws deep in the pack. Sometimes we refer to this kind of snowpack as “tired” or “old”, as snow can stabilize over time when weather conditions are benign for extended periods of time. This is where we are now, almost three weeks after the last major weather event, and we don’t have any significant weather on the horizon to be concerned about.
While the likelihood of triggering an avalanche is low, it doesn’t mean it is impossible. Stability tests have been varied, with the majority showing increased stability, and a lack of red flags from backcountry travelers, including forecasters and avalanche courses. The weak layer of concern at the base of the snowpack has gained strength and faceted crystals have rounded. While we are confident in good stability, we caution that the kind of structure we have could produce an avalanche in very isolated locations. Where that could happen is hard to pinpoint, but pay attention to slab thickness and distribution. Problem areas could be where the slab is thinner, such as near buried rocks, near exposed rocky areas, or on the peripheral boundaries of seasonally scoured and loaded slopes.
We have not experienced red flags such as avalanches, cracking, or whumphing and collapsing for a long time. These are red flags and if you encounter them they are bullseye clues for avalanche sensitivity.
Our advice is to continue to practice safe travel protocol as a habit and discipline, even when the avalanche hazard is low.
Below is a snowpit from yesterday showing the upside-down structure, weak layer at the base of the snowpack, and a stability test that did not produce propagation. More info in observations.
We received 2″ of new snow at IM Snotel in the last 7 days.
The next chance for snow is expected late Saturday and into Sunday. But this looks like a weak pulse that may only produce a dusting.
National Weather Service Anchorage AK
250 AM AKST Thu Jan 12 2023 .
DISCUSSION… Weak east to northeast flow will generally persist through Friday as a series of weak easterly waves rotate into the Gulf around a slow moving upper trough off to the south. The best chance for periods of light precipitation will be focused along the eastern Kenai Peninsula and western Prince William Sound region through early this afternoon as one of these waves pushes northwest into the Kenai Peninsula before shearing apart by this evening. The highest precipitation chances will be focused near Portage Valley and south/east, with most of the Chugach Front Range along with Hatcher Pass expected to remain dry through the start of the weekend. Snow levels will hover between 400 and 900 ft through tonight, resulting in mainly light rain at times through the eastern Turnagain Arm and Portage Valley. A break in the light snow and low elevation rain is expected for most of the day Friday. However, higher precipitation odds will return between Friday evening and Saturday morning across the eastern Kenai Peninsula as well as for Valdez and Cordova as a low moves into the southern Gulf and pushes a weak front towards the north Gulf Coast. At least a modest increase in easterly winds is likely ahead of the front, with the strongest and gustiest winds developing across higher peaks and ridges across the eastern Kenai Peninsula from late Friday into Saturday.
NWS AVG Forecast here.
NWS point forecast here.
Marmot Weather Station here.
Independence Mine Snotel here.
State Parks Snow Report and Motorized Access information here.
XC trail grooming report for Mat-Su, Anchorage, and Kenai here.