Summit & Central Kenai Mtns

Recent Avalanches: A natural avalanche was reported today (Feb 9) on Templeton Mtn. It is possible the avalanche released last night due to high winds transporting fresh snow.  Otherwise, the last reported avalanche was a wind slab avalanche on Tributary Mtn on Jan 30. The slab was around a foot deep and about 80ft wide. That being said, visibility in Summit earlier this week has made it difficult to see avalanche activity. If you see recent avalanches, please consider submitting an observation.

Weather Recap: Last weekend around 5″ of new snow fell accompanied with northeast winds gusting to 30 mph. From Tuesday into Wednesday Summit Pass was mostly cloudy and windy with ridgetop winds averaging 20 to 30 mph and temperature increasing from single digits to low 30’s F. A storm arrived on Thursday afternoon bringing 1″ of snow overnight, northeast winds gusting to 60+ mph and above freezing temperatures in the pass.  Friday delivered 35 mph gusts by the highway, 50+ mph on ridgetops, a few inches of snow, and above freezing temperatures (35 F).

Weather Forecast: The storm that arrived on Thursday is forecast to bring cloudy skies and up to 6″ of new snow to Summit over the weekend with strong winds. On Friday night into Saturday morning sustained winds 20 to 30 mph from the southeast are expected with 40+ mph ridgetop winds, a few inches of new snow, and temperatures dropping to the mid 20’s F. Saturday is likely to receive another few inches of snow and sustained southerly winds averaging 15 to 25 mph with ridgetops gusts 30 to 40 mph and temperatures averaging 20 to 30 F. On Sunday the sun may shine through cloudy skies as the storm begins to break up with ridgetops winds from the south averaging 10 to 20 mph, 30+ mph gusts a few lingering flurries and temperatures averaging 15 to 25 F.

Recent natural avalanche on Templeton Mtn likely releasing on Feb 9. Photo by Katie Mohn 2.9.2024

Strong winds are forecast out of the east on Friday night then switching out of the south on Saturday which will cause wind slabs to form on multiple aspects. These winds are expected to transport new and old snow into touchy wind slabs 1 to 2′ deep at all elevations that is affected by the wind including below treeline.  Wind slabs can be found on the leeward side of wind affected features such as below ridgelines, convex rollovers, and in cross loaded gullies. Red flags such as natural avalanches, blowing snow, and shooting cracks indicate that you can trigger an avalanche. The safest option is to avoid steep wind loaded slopes instead riding lower angle terrain not affected by the wind until the snowpack has had time to settle.

It is possible that fresh wind slabs will also be forming over a persistent weak layer buried 1′ deep that will increase the likelihood of triggering a much larger avalanche. More about this in our problem 2.

Lonestar Mtn with this week’s winds scouring the windward slopes and loading leeward slopes. Photo 2.6.2024

The Alaska Railroad at Mile 43 Peak weather station records wind patterns similar to Summit’s ridgetop winds. This wind rose is showing very strong winds from the east northeast. 

The weak sugary snow and surface hoar that formed during January’s period of cold clear weather is now covered by 1′ of snow.  This weekend’s strong winds and new snow will add stress to this layer however, it may not be enough to cause natural avalanches. If that is the case then this layer may not show signs of instability until it is triggered. It has been observed from the highway to 2500′ making it a widespread issue including areas below treeline that has been relatively safe for most of the season. We recommend staying out of avalanche terrain (30 degree slopes or steeper) until the storm subsides and we get a better idea as to how sensitive the layer is. It is also important to mention that while red flags such as cracking, collapsing, and recent avalanches can provide some information, persistent slabs may not give you any clues until they avalanche.

It has been over two weeks since a glide avalanche was reported in Summit Pass. As always try to avoid traveling under these glide cracks because it is possible for new or old cracks to release into an avalanche.