Northern San Juan
AvalancheAnonymous · Jan 10, 2016 · Northern San Juan
Weather
Observation made on the 9th: Broken skies all day with light winds out of the NNW Lightly transporting new snow
Snowpack
Observed HN from the 5th anywhere from 30cm Btl to 45cm N/Atl extremely low density. Localized cracking around skis while skinning but very little consolidation within new snow. Sluffing on open slopes over 35 degrees common on all aspects Atl and kicking cornice produced small D1 sluffs isolated to the area impacted. Profile on NNW Ntl showed the PWL of concern to be 120 cm below the surface. Slab was right side up, Starting with F hard snow and progressing to Pencil and was supportive to boot penetration (PB 55cm). ECT in this area showed moderate Propagating results (ECTP 17 SC Q2) 120 cm below the surface. Classic Low probability/ High Consequence type of scenario here. Surface of the snow already showing NSF development with our extremely cold temps (.5-1)
Avalanche
Multiple D1 point releases on all aspects Atl on slopes above 35 degrees. Most of the runout distances were limited by underlying terrain. Of note were two D2 loose snow avalanches running 600'-800' and entraining the entirety of the new snow. E aspect Atl