This is Mark Staples with the avalanche forecast for Thursday, January 16th, at 7:00 a.m. sponsored by Spark R&D and Polaris. This forecast does not apply to operating ski areas.
Yesterday high temperatures reached the low to mid 30s F in most areas under sunny skies. Snow on many sunny slopes became a little damp
This morning, temperatures are 5-7 degrees warmer than yesterday morning. Winds are blowing 15-20 mph gusting to 30 from the W and SW, except near Cooke City with light winds from the NW.
Today should be another warm one with sunny skies and a few high clouds. Temperatures should easily climb above freezing into the 30s F again. It’ll be breezy with winds from the W and SW continuing 15-20 mph gusting to 30.
Get ready for a big change in the weather. It cools off tomorrow with some snow falling into Saturday (only a few inches). On Saturday, the jet stream comes straight down from the north bringing some of the coldest air of the season with mountain temperatures well below 0 F.
Persistent slab avalanches remain possible on a layer of facets 1-3 feet deep. This layer is the weakest near Lionhead as well as many lower elevation areas where people ski like Specimen Creek and Bacon Rind. A large, naturally triggered avalanche was spotted from the air on Red Mountain in the southern Madison Range yesterday just west of Ernest Miller Ridge.
Even though the likelihood of triggering one of these persistent slab avalanches is dropping, this isn’t a problem to mess with. UAC Moab forecaster, Eric Trenbeath wrote a great post about this exact situation years ago when he was caught in one of these avalanches when the danger was “only moderate.”
The snowpack is deeper and appears stronger in most snowpits near Cooke City and Island Park. I’m not totally sure why, but Cooke City (scroll through all the Cooke observations) has also had more avalanche activity than most other areas with some large ones breaking up to 4-6 ft deep. Cooke does have much more high alpine terrain which could be a factor. Near Island Park the snowpack is pretty deep with similar layering, but there has been very little reported avalanche activity.
Old wind slab avalanches can also be triggered near ridgelines. Look for signs of previous wind drifting to avoid these places.
The key today is terrain selection. Slopes less than 30 degrees in steepness that aren’t steep enough to slide are always the safest option. If getting onto steeper terrain, remember that bigger avalanches happen in bigger terrain, so consider smaller terrain with a clean runout to reduce the consequences of a slide if one happens. Today the avalanche danger is MODERATE.
Wind has been the dominant weather factor in the mountains near Bozeman and Big Sky making old wind slab avalanches the main concern. Winds have done their work and don’t have much snow left to transport.
Persistent slab avalanches have become mostly unlikely in many areas where the snowpack has gotten deeper, but they are a lingering concern in places with shallower snow. I found both of these situations while skiing yesterday in Beehive and Middle Basins. Ian and Dave found a similar story in Portal Creek and I found the same thing on Mt Blackmore.
Heads up - At lower elevations, especially near exposed rocks that add extra heat to the snow, wet loose avalanches will be a concern today. Ice climbers are particularly vulnerable and should watch for heating of the snow. One observer found many wet slides covering the trail along the Unnamed Wall in Hyalite yesterday.
Today, the avalanche danger is MODERATE with heightened avalanche conditions in areas with previous wind loading, areas with thin snow, and lower elevation areas where the snow becomes wet.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
Avalanche Fundamentals with Field Session for non-motorized travelers during the last weekend of January.
Every weekend in Cooke City: Friday at The Antlers at 7 p.m., Free Avalanche Awareness and Current Conditions talk, and Saturday from 10 a.m.-2 p.m. at Round Lake Warming Hut, Free Rescue Practice.
KING AND QUEEN OF THE RIDGE
Do you like to hike? Do you like to ski/ride? Then the King & Queen of the Ridge on 2/1 is for you. Hike, ride and raise money for the Friends of the Avalanche Center at Bridger Bowl this year! Join this fun event to promote and support avalanche safety and awareness! Fundraising prizes for the top 5 individuals who raise over $500. No racing is necessary to compete for the fundraising prizes. Info to fundraise is HERE or donate here.
***Race participants for the King and Queen of the Ridge must register separately with Bridger Bowl here***
Thank you for sharing observations. Please let us know about avalanches, weather or signs of instability via the form on our website, or you can email us at mtavalanche@gmail.com, or call the office phone at 406-587-6984.