Tetons

Two days of strong winds and easily transported light density snow have created easily triggered surface slabs a foot or more in depth on steep, lee slopes and near ridges at upper elevations and in steep ravines or wind exposed areas at mid elevations. The drifted new snow rests on slick sun crusts and wind packed snow and slides will move quickly. Yesterday a skier triggered a slide at the base of the Titty Mouse ridge south of Teton Pass. At low elevations the snowpack is mostly stable and avalanches are unlikely.

A strong area of low pressure will move across the region bringing moderate to heavy snowfall Tuesday night through Wednesday. Snowfall amounts by Wednesday evening will be 12 to 15 inches in the Wyoming and Salt ranges, 6 to 12 inches in the Tetons and 5 to 7 inches in the Togwotee Pass area. Temperatures will be in the upper teens Wednesday morning and warm only a few degrees during the day. Ridge top winds will be southerly overnight at 20 to 25 miles per hour then veer to southwesterly during the morning and increase to 40 miles per hour with stronger gusts before slowing in the afternoon.The new snow will be falling on weak, light density snow over wind crusts, wind pack and surface hoar depending on local variations. This combination with strong winds will create easily triggered slabs that will build rapidly through the day. The avalanche hazard is expected to rise to CONSIDERABLE in the Tetons, MODERATE in the Togwotee Pass area and may build to a HIGH rating in the Salt River/Wyoming Ranges.