This is Ian Hoyer with the avalanche forecast for Friday, March 14th, at 7:00 a.m. sponsored by Bridger Bowl and Beartooth Adventures. This forecast does not apply to operating ski areas.
There are generally 5-8” of new snow (0.4-0.9” Snow Water Equivalent) across the advisory area, with up to 10” at one snow sensor near Big Sky. Winds dropped off yesterday as the cold front moved through and are blowing 10-20 mph out of the southwest to northwest this morning, with gusts of 20-40 mph. Temperatures are in the teens and 20s F.
Snowfall has mostly wrapped up early this morning. Snow showers today and tonight will only leave a dusting in most places, but there may be spots that see up to 2” by tomorrow morning. Winds today will be out of the west and southwest at 10-20 mph. Mostly cloudy skies this morning will likely clear this afternoon around Bozeman and Big Sky, while staying cloudy elsewhere. High temperatures will be in the 20s and low 30s F.
All Regions
Wind Slabs avalanches are the primary concern today, where the new snow has been drifted into deeper, more cohesive slabs. These drifts may be up to 2 ft deep and could be easily triggered today, but I don’t expect these deeper drifts to be widespread. Be especially on alert in areas where you’re finding more new snow and beneath ridgelines and cornices where the deepest drifts are likely to form. Look and feel for signs of wind effect and avoid wind drifted slopes to avoid most of the avalanche hazard today. Shooting cracks or recent avalanches are the clearest signs of instability. If you see these signs, stay off steep slopes and give the new snow some time to bond.
In spots where the snow piled up deepest, you might be able to trigger a dangerous Storm Slab avalanche on a slope without wind effect, but I mostly expect the new snow to have bonded well to the old snow surface and to be right-side up.
If the sun comes out this afternoon, the new snow will quickly get wet and make for Wet Loose avalanches. These slides won’t generally be very deep, but could pick up speed and run far on firm crusts that formed over the last week.
Near West Yellowstone, there is a weak layer of facets buried 2-3 ft deep that has been dormant. These probably won’t be an issue today, but we shouldn’t forget about them as they could wake up in the coming days as more new snow stacks up.
The avalanche danger is MODERATE today across the advisory area.
