Rapid snowfall and strong westerly winds are creating wind slabs on lee slopes at mid and upper elevations. The chance of people triggering slides will increase through the day. At low elevations periods of rain will further weaken the poor snowpack and increase the chance of slides in very steep areas like ravines.
Moderate to heavy snowfall, strong westerly winds and warming temperatures will combine to create easily triggered soft slabs on lee slopes at mid and upper elevations. Avalanches as deep as 18 inches should be expected by afternoon. The slabs are forming on slick sun crusts and wind packed surfaces. Evaluate snow and terrain carefully to identify areas of concern.
Light snow is possible overnight with flurries possible Monday before a dry ridge of high pressure moves into the area Monday evening. Temperatures at 9,000 feet will be in the single digits in the morning then warm to the mid teens. Winds will continue at 25 miles per hour from the west overnight then slow to 10 miles per hour from the north to northwest by late Monday morning.The general avalanche hazard is expected to be MODERATE. Monday backcountry travelers in the Tetons and Southwest Trails/Greys River areas will have the potential to easily trigger firm wind slabs to 18 inches in depth on steep, lee slopes particularly near ridge crests or areas with good cross-loading. Temperatures will be low Monday but be alert to poorly bonding graupel on smooth crusts. Periods of sunshine will also increase the chance of triggering slabs and sloughs on sunlit aspects.In the Greys River/Southwest Trails area and The Togwotee Pass area weak snow at the base of the snowpack still holds the potential for users to trigger persistent slabs to three feet in depth on steep slopes.
