|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.
Yesterday at least one new glide avalanche was observed. What was most notable was that new cracks continue to appear and grow. The West facing terrain on Cornbiscuit now is littered with small, progressing cracks that make it essentially un-skinnable. Magnum West face and South face both have growing cracks and even Sunburst’s “mini” glide crack is getting more pronounced. This all indicates snow on the move. Pick your route carefully in the 1000′-2500′ elevation band.
This current wet snowpack, combined with mostly sunny skies and temperatures above freezing, has us continuing to think glide activity is likely. Our message remains the same: AVOID being under glide cracks and respective runout zones. To be in the wrong place at the wrong time when a glide releases could likely be deadly. Considering the motorized up-track is threatened by cracks, we are recommending that people do not travel on the up-track or in runout areas along Seattle Ridge.
Cornbiscuit glide cracks. 4/16
Wet loose avalanches have been occurring for the past few days. These have been naturally occurring with warm temperatures, rain and direct sunlight affecting surface snow and mostly confined to the 1000′-2500′ elevation band. Expect more of the same today and potentially an increase with clearing skies. The few inches of new snow that fell over the past few days above 2000′ is primed if heated enough and lower elevation snow is completely saturated. Human triggering a wet loose avalanche in steep terrain is likely. Pay attention to ski penetration and punchy snow as well as roller balls both natural and travel initiated. Remember wet loose avalanches can be hard to escape once initiated and particularly hazardous if they push you into a terrain trap. Take into account what terrain is above you and what you may have to cross under to get back to your car when venturing to cooler snow in the Alpine.
Wet loose activity on Seattle Ridge with glide cracks and old glide avalanches.
At elevations above 2,500′ and in the Alpine the snowpack is generally stable. There are a few things to watch for if traveling in the upper elevations:
– Lingering wind slabs that could be triggered in steep, unsupported terrain.
– Cornice falls (we have yet to see cornices start falling in the Alpine but this could happen any day with the warm temperatures and direct sunlight).
– Wet loose avalanches on steep solar aspects, both natural and human triggered. These have been predominantly confined to the 1000′-2500′ elevation band but this may change and be higher with heating throughout the next two days.
Yesterday was mostly cloudy in the morning with isolated rain and snow showers trending to partly cloudy by mid afternoon. Temperatures were in the upper 20Fs to upper 30Fs. Winds were light and easterly.
Today and tomorrow are forecasted to be mostly to partly sunny with temperatures in the high 30Fs at 3000′ and the high 40Fs at 1000′. Winds will be light and variable. Scattered showers will be a possibility Monday afternoon with increasing clouds and precipitation on tap for Tuesday.
|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: Silvertip Creek
|Observation: Seattle Ridge
|John Sykes Forecaster
|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