Turnagain Pass Avalanche Forecast

With a bit of a “Groundhog Day” feel our weather remains cold and clear and our snowpack is in a holding pattern of sorts. It has been 14 days since the last measureable precipitation and a week since the beginning of the Northwest ‘wind event’. Several large wind slab avalanches have occurred over the past week, most of these in the Summit Lake area South of the forecast zone. However, we did get a report of a suspected natural wind slab avalanche in the Girdwood Valley Sunday, on the North end of the forecast zone. This was on an upper elevation, Southwest facing slope, under Goat Mountain. 

If you are headed to the mountains, the avalanche conditions are in a ‘Normal Caution’ regime.  LOW avalanche danger doesn’t mean no avalanche danger. This means avalanches are unlikely, but not impossible. Things to watch for and keep in mind will be:

Wind Slabs:
Old, stubborn and hard wind slabs could pop out in steep and rocky terrain. This is most likely where weak faceted snow sits under shallower hard slabs – usually found in the steep rocky thin zones. Watch for hard snow over weak loose snow as well as shooting cracks and whumphing noises. If winds ramp up today look for active loading along ridgelines however, there isn’t much snow left to move…

Loose Snow (Sluffs):
Dry sluffs on steep slopes are getting larger in areas harboring loose surface snow – watch your sluff! Also, with direct sun and depending on what the winds do today the Southerly aspects could become damp or wet in the afternoon. This may cause natural wet/damp loose snow avalanches on some steep Southerly slopes and/or make it more likely to trigger one.

Glide Avalanches:
Glide cracks continue to slowly open in the advisory area. These could release at any time, watch for the cracks in the terrain and avoid being under them.

Cornices:
There was a natural cornice fall in the Kern drainage observed on Friday (exact release time frame unknown). Cornices should always be given a wide berth from above and limit exposure time traveling underneath.

Persistent Slabs and Deep Slabs: 
There are various weak layers in our thin snowpack; the snowpack is roughly half of what it normally is this time of year. Buried surface hoar sits 1-3+’ below the surface and faceted snow sits in the mid and base of the pack. These various weak layers with varying degrees of strength are in a dormant stage due to a lack of weather and ample time to adjust. Although this means the layers are not producing avalanches, it doesn’t mean an outlier can’t occur which causes a large avalanche breaking deeper in the pack. 

Cornice in Petersen Creek yesterday. This is a good example of a cornice that could break farther back than expected.