|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.|
Nearly all the activity we’ve seen recently can be classified under wind slab. Fortunately everything we’ve seen has been low volume and isolated to small pockets. The photo below is from 2 days ago on Tincan.
Since we just got a significant additional load of new snow and wind, this concern is worse today. Snowfall was heavy enough yesterday to limit visibility and prevent anybody from getting above treeline. We haven’t seen firsthand the areas of highest concern, but we know it’s been snowing and blowing.
South facing slopes will add another layer of complexity. Multiple layers of buried sun crusts can be found on sunny aspects. We don’t know how those layers will react to the moderate additional snow load, but it’s worth considering that new snow doesn’t bond easily to slippery crusts. Stability aside, those crust layers may affect the quality of skiing and riding on south aspects.
In areas that were not wind affected we can expect loose snow to sluff easily in steep terrain. Anywhere the wind didn’t stiffen up the surface and slope angles exceed the mid 30 degrees you should expect snow to sluff and entrain volume on the way down. This could be a problem if surprised or in steep channeled terrain.
Snow totals for the last 24 hours
Turnagain Pass snotel – 8 inches
Alyeska midway – 10 inches
Summit lake mountains – 6 inches
Wind has been trending from the southeast in Turnagain Pass with variations depending on the location. Temperatures are warmer than they’ve been, producing mixed rain and snow at sea level. Above 1500 feet the snow is dry.
Today’s weather calls for scattered snow showers. The bulk of the precipitation has passed. Expect a slight cooling trend and a diminishing trend with the wind.
Wendy will issue the next advisory tomorrow morning, March 31st.
|11/27/23||Turnagain||Avalanche: Tincan Ridge||Schauer/ Stiassny Forecaster|
|11/26/23||Turnagain||Observation: Road report: Slide with dirt on Repeat offender||Anonymous|
|11/26/23||Turnagain||Observation: Pete’s North||Ben Sullender|
|11/25/23||Turnagain||Observation: Tincan trees||John Sykes Forecaster|
|11/21/23||Observation: Spokane Creek||John Sykes Forecaster|
|11/19/23||Turnagain||Observation: Magnum – PMS Bowl||Schauer/ Cullen/ Jonas Forecaster|
|11/19/23||Other Regions||Observation: Sunnyside/Penguin||Jose Ramos-Leon|
|11/19/23||Turnagain||Observation: Eddies||Andy Moderow|