|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.
|Size (D scale)
|Unlikely to bury a person
|Can bury a person
|Can destroy a house
|4 & 5
|Can destroy part or all of a village
Yesterday Alpine weather stations recorded above freezing temperatures for most of the day. The weather station on Max’s Mountain (3200′) above Girdwood recorded a high of 42F at 5 pm. Some small wet loose avalanche activity was observed as well as some “sticky” surface conditions on slopes getting direct sunshine. No new slab avalanche activity was reported. After a night with temperatures dipping below freezing and clear skies expect crust in the morning on surfaces influenced by yesterday’s warming. Watch for changing conditions again during the heat of the day. The Valentine’s near surface facets sitting around a foot below the surface is the main persistent weak layer of concern. As the days pass since our last loading event the likelihood of triggering an avalanche has decreased. However warming can sometimes make slabs resting on persistent weak layers more easy to trigger and stability tests are still showing that this layer has the potential to avalanche.
What to keep in mind today:
– Wind-loaded, steep, unsupported slopes are the most suspect for popping out a slab that may be sitting on weak snow.
– Larger and more dangerous avalanches are possible in the Summit Lake and Johnson/Bench peak area where a thinner snowpack exists with multiple weak layers.
– SUN EFFECT and moist/wet sluffs on or under steep rocky southerly terrain. On wind protected, shaded, steep slopes watch for facet sluffing.
– Cornices. Warmer temperatures at higher elevations can help loosen these monsters and with good weather and ridgeline travel, don’t forget to give cornices a wide berth.
And remember to practice safe travel protocol!
Slab over the Valentine’s facets, 2.22.19. This set-up has been noted across the advisory area.
Wet loose avalanches on Goat, 2.25.19
Glide cracks are unpredictable, not associated with human triggers, and can release without warning at any time. The best way to manage this problem is to avoid traveling on slopes directly below glide cracks. A short list of known cracks in popular zones: Magnum, Lipps, Seattle Ridge, Eddies, Lynx Ck. See a new glide crack or one that appears to be opening up? Please snap a photo and send us a quick ob!
Glide cracks on Magnum, 2.25.19. Photo: Nikki Champion
Yesterday: Clear and sunny! Temperatures were in the 30Fs to low 40Fs in the Alpine and in the teens to mid 20Fs at lower elevations. Winds were very light and easterly. Overnight temperatures in the Alpine were in the low 30Fs to high 20Fs. Valley bottoms were in the single digits to low teens, skies were clear and winds were calm.
Today: Another day of sunshine and a temperature inversion. Expect 30Fs-40Fs at upper elevations and teens to 20Fs at lower elevations. Winds remain light. Temperatures will drop again overnight with clear skies and the inversion will continue.
Tomorrow: The ridge of high pressure is still very much in place and the current weather pattern is expected to continue into the weekend. We may see a few more clouds later in the week but overall more of the same. Seems like a good time for a snow dance! Marvelous March powder???
|Temp Avg (F)
|Snow Depth (in)
|Center Ridge (1880′)
|Summit Lake (1400′)
|Alyeska Mid (1700′)
|Temp Avg (F)
|Wind Avg (mph)
|Wind Gust (mph)
|Seattle Ridge (2400′)
|Observation: Kickstep NE Bowl
|Observation: TinCan Backdoor/ Center Ridge
|AAS L1 Turnagain
|Avalanche: Lynx Creek
|Observation: Turnagain, Seattle, Mt Ascension
|Silverton Mountain Guides
|Observation: Tincan Trees
|Dalpes/Thamm/ Schauer Forecaster
|Observation: Seward Highway across from Johnson Pass TH
|Avalanche: Base of Seattle Ridge
|Troy Tempel, Thomas Lees, .Josh Bollaert, Damian Naquin
|Observation: Lynx creek