Tetons

At the mid and upper elevations strong southwest winds and new snow will combine to rapidly increase the avalanche hazard. New soft slabs up to 18 inches in depth will form upon excellent sliding surfaces. These slabs are likely to be easily triggered by humans and release spontaneously in response to rapid wind loading as they gain volume and depth. Safe travel in avalanche terrain today requires conservative decisions, careful route finding and good travel habits. Local knowledge and experience are essential. Avalanches are unlikely below an elevation of 7,500 feet.

The upper level low associated with this frontal passage was located over Central Idaho this afternoon. Periods of moderate to heavy snowfall are likely before the precipitation tapers to light snowfall after midnight. Another 4 to 9 inches of new snow accumulation is possible by morning. On Sunday a very cold unstable arctic air mass will produce bursts of snow with an additional 2 to 4 inches of new snow accumulation by Sunday night. Ridge crest winds will be northwesterly to southwesterly at 15 to 25 miles per hour. Temperatures will be in the single digits above and below zero.The general avalanche hazard at the mid and upper elevations (7,500 to 10,500 feet) is expected to be CONSIDERABLE. Soft surface slabs up to two feet in depth lie upon excellent sliding surfaces and are expected to be very sensitive to human triggers. Natural avalanche activity is possible. At the lower elevations (below 7,500 feet) the general avalanche hazard is expected to be LOW.