This is Mark Staples with the avalanche forecast on Thursday, April 17th, at 7:00 a.m. sponsored by Highline Partners and Uphill Pursuits. This forecast does not apply to operating ski areas.
Winter is back with a vengeance as temperatures started plummeting yesterday around 5pm and it’s snowing hard this morning. Temperatures this morning are mostly in the mid teens F. Winds this morning are blowing 5-10 mph gusting to 20 mph at ridgetops mostly from the north except in the Bridgers where winds are coming from the east with gusts hitting 40 mph.
6am snow totals are:
- 7” snow (0.6” water) - Bridger Range
- 5” snow (0.5” water) - Cooke City area
- 3” snow (0.2” water) - Big Sky area
- no new snow near West Yellowstone and Island Park
Today will be cold, cloudy, snowy, and windy as the center of a low pressure trough circles overhead. Expect winds to increase by midday blowing from the north-northeast 20 mph gusting to 40 mph. Temperatures will struggle to break into the low 20s F.
Snowfall should end tonight with most places getting another 2-4”, but the Bridgers could get a bit more. Clearing skies tonight could allow temperatures to drop into the single digits F. The Beartooth Mountains and Red Lodge area could do well with snowfall today. (Red Lodge Mountain opens for skiing and riding tomorrow through the weekend)
Looking ahead - The jet stream is a bit disorganized with no major systems lined up, but the overall trend through the rest of April is cool and wet. Friday & Saturday have clear skies, then snowfall returns early Sunday morning into Monday.
Wind slab avalanches will be the most likely slides to trigger today. With gusty east winds this morning and stronger north-northeast winds expected today, wind slabs will grow larger and easier to trigger as the day progresses. HEADS UP - easterly winds will create abnormal loading patterns.
Storm slab avalanches will be something to consider especially as more snow accumulates. The storm is right-side-up this morning which is good thing. Today, brief periods of higher snowfall rates or a little bit of warming could create a slightly cohesive slab in the new snow. Look for signs of instability in the new snow by looking for cracking, jumping on small test slopes, and stepping above your partner’s tracks. At a minimum expect sluffing of the new snow.
Today the avalanche danger is CONSIDERABLE on wind loaded slopes. Seek out soft powder on slopes untouched by the wind where the danger is MODERATE. Assess stability in the new snow before getting into steeper terrain.
Wind slab avalanches will also be a concern in the Gallatin and Madison Ranges but with less new snow they will be shallower. Otherwise, riding slopes untouched by winds may be “dust on crust” and there will only be minor sluffing of the new snow on the hard icy surface underneath.
Today the avalanche danger is MODERATE.
With the snowpack refrozen and no new snow this morning, skiing and riding conditions will be a bit rugged. Avalanches are unlikely and the avalanche danger is LOW.
If you encounter an error with our observation submission platform, please email your observations to mtavalanche@gmail.com
Bridger Bowl Ski Area is closed for the season, and uphill travel is allowed. Please give employees and machinery plenty of room as they work to clean up from the season. Backcountry conditions will develop as spring storms impact the range. There are no ski patrol services, avalanche mitigation or terrain closures as conditions evolve. Call 911 for any incidents requiring outside assistance.
Our last daily avalanche forecast will be Sunday, April 20th. We will issue updates on Mondays and Fridays through the end of April.