Northern San Juan

Snowpack

Ann Mellick · Mar 31, 2011 · Northern San Juan

Weather

Overall sunny and mild, but cool with blustery NW winds up high. Puffy fair weather cumulus in the PM

Snowpack

Snowpack warming today. Intense solar radiation and warming temperatures liberating lots of free water. Extensive roller balls and sluffing on virtually all aspects, especially up high, where snow has remained cooler (up til now). Snowpack remains highly aspect and elevation dependent- continued transition. Recent cool weather had refrozen snow, which began to warm rapidly today. Some cracking/collapsing on easterly slopes below treeline- failing just below the dust layer (down ~6" from surface). Also, wet "sheeting" of surface snow on dust layer. Meanwhile, temps remained cool in the alpine zone with plenty of dry snow swirling around along ridgelines from strong northwesterly winds. Not much slab formation, but surface was stiffening. Northerly slopes above treeline a mixed bag of settled powder to stiffer thin surface slab sitting atop older windslabs below. Sun is getting higher so affecting northerly terrain as well, but hitting much more obliquely, thus less intense. However, persistent weak layers remain intact on these slopes so slabs may become an increasing problem with continued warming.