New snow, moderate to strong winds and continued snowfall have heightened the avalanche danger. Above 7500 feet, new wind slabs that will be sensitive to backcountry riders and skiers have formed on a variety of snow surfaces. Additional loading of the snowpack will also make deeper instabilities more susceptible to failure. If triggered these deeper slabs will be large to very large and are likely to carry severe consequences to anyone involved. Avalanches below 7500 feet are unlikely today except in isolated pockets. Conservative decision making and an understanding of the snowpack is essential to safe backcountry travel today.
Dangerous deep slab avalanches 2 to 5 feet in depth could be human triggered on distinct persistent weak layers that were buried in mid-January and December. New loading will further increase the sensitivity of these slabs and failure could occur today to the weight of a single person, to the movement of a surface slab, or possibly release naturally.
Above 7500 feet, new soft surface slabs will be sensitive to backcountry travelers in areas prone to wind loading with depths to one foot.
( Discussion is generated from the previous day's afternoon forecast. )Snow is to fall overnight and throughout the day on Thursday. The heaviest snowfall is to occur this evening and tonight. Six to eight inches is expected by sunrise with another three to five inches during the day. Mountain temperatures are to reach the upper teens Thursday and winds will veer southwest to west with 25-35 mph averages.The general avalanche hazard will increase from Moderate to Considerable above 7500 feet if enough snow and wind occur to form new substantial wind slabs which would also increase the sensitivity of persistent weaknesses in the snowpack. Avalanches below 7500 are not expected tomorrow.
