Turnagain Pass

Yesterday as the sun poked out late in the afternoon a wet loose avalanche on Raggedtop mountain in Girdwood triggered a wet slab. Observers also noted new wet loose snow avalanches around the region. Rain/snow line was approximately 2700′. Conditions below that were described as “slop” in the saturated surface snow and above that new snow easily formed roller balls. A few skiers remarked on the “parade of pinwheels” initiating from their turns. There was clearing last night and a crust formed on the surface of the snowpack. This will slow snowpack warming down in the morning. However, the temperatures are forecast to rapidly rise and it is supposed to be clear and sunny with calm winds. Expect human triggered wet loose avalanches to become likely on solar aspects and watch for naturals later in the day. The wet loose avalanches may trigger wet slabs. If you do decide to recreate today pay attention to the depth you are sinking in and get off the slope if the snow is over your boot tops or your machine is trenching in. Watch for roller balls.  Expect loose snow moving to entrain more as moves downhill. Any fresh snow in the Alpine may be especially reactive on solar aspects. If the clouds move in early and trap the heat, fresh snow on shaded aspects may also become more reactive. Wet loose and wet slab avalanches today could be large and dangerous.

Wet slab avalanche on Raggedtop triggered by loose snow off of the rocks. 

Wet loose avalanches on Raggedtop initiated when the sun came out. 

Storm slabs: The precipitation over the past few days in the Alpine has fallen as snow. This rain/snowline has fluctuated so pay attention to changing conditions. Locations closer to the coast may have received up to a foot above 3000′. This storm slab may be especially reactive as temperatures rise today and on solar aspects as the sun hits. The winds have been strong as well and this may have created deeper slabs on leeward aspects. Look for wind drifts or pillowed snow, watch for cracking and remember conditions could change rapidly as the sun warms the snow. 

Cornices: This new snow and wind will have also added to already large cornices.  It’s that time of year where the snowpack is warming up and cornices will begin to break. Give cornices a wide berth.

In the Alpine on Northerly shaded aspects above the rain/snow line triggering a slab avalanche 1-2′ thick on weak faceted snow is still possible. The old slab/facet combo remains suspect and may be more tender with the additional snow and wind loading.