GNFAC Avalanche Forecast for Sat Feb 22, 2025
<p><span><span><span><strong><span><span>Persistent Slab avalanches </span></span></strong></span></span></span><span><span><span><span><span><span>remain the primary concern. Yesterday, a rider in Tepee Basin triggered an avalanche from the bottom of a slope that broke up to 3 ft deep and 250 ft wide, partially burying him, with just one arm and one leg sticking out of the snow (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34301"><span><span><span><span><span><… and photos</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>). Fortunately his partners got him out quickly and unharmed. Nearby, in the Taylor Fork, Alex triggered a 100 ft long shooting crack (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34298"><span><span><span><span><span><…;). This shows us the weak layers that formed in late January remain touchy. Many of these slides are happening far below ridgelines, on mid elevation slopes with trees around (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34264"><span><span><span><span><span><… video</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34264"><span><span><span><span><span><… Canyon photos</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>). Don’t get lulled into a false sense of security by seeing tracks on steep slopes. It could be the 2nd, or the 10th, rider that hits the sweet spot and triggers the whole slope.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Wind Slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> are a more isolated concern, but keep your eye out for drifts that haven’t bonded yet.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Avalanche conditions remain dangerous and the avalanche danger is CONSIDERABLE.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Wind Slabs avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> are the biggest concern across the rest of the advisory area today. Be on the lookout for freshly formed wind drifts or older drifts that haven’t yet bonded to the snow beneath them. I expect new drifts to be pretty isolated, but they could be easily triggered. A stiff snow surface and cracks shooting out in front of you are clear signs that you’ve found an unstable drift.</span></span></span></span></span></span></p>
<p><span><span><span><strong><span><span>Wet loose avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> are also a concern as temperatures warm and surface snow melts. After warm temperatures and sunny skies yesterday with a good refreeze overnight, I don’t expect a ton of activity today. We did get a report yesterday of a decent size wet slide in Gallatin Canyon, so be on alert today at low elevations (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/34307"><span><span><span><span><span><… Canyon details</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>, </span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=LYqruI9gUp0"><span><span><span><span><s… Canyon video</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>). Crusts breaking down and the snow surface getting sticky and wet are signs that wet snow danger is increasing.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>The avalanche danger is MODERATE today.</span></span></span></span></span></span></p>
Special Note - Roof avalanches
Many roofs have lots of snow on them that may come crashing down as a roof avalanche during the first big warm-up with strong sunshine. Avalanche fatalities from roof avalanches are not uncommon. Kids are especially vulnerable because they often play near houses while no one is watching.
Pinwheels and small wet slide in Gallatin Canyon
From youtube comment: "Sooooo many pin wheels coming down in the Gallatin canyon today on my way home from work. I was driving and couldn't get a full look, but half way through the canyon, it looked like a whole, relatively small, slope slid, maybe propagated 50-75ft on the west facing side of the road."
Wet snow in Gallatin Canyon
Sooooo many pin wheels coming down in the Gallatin canyon today on my way home from work. I was driving and couldn't get a full look, but half way through the canyon, it looked like a whole, relatively small, slope slid, maybe propagated 50-75ft on the west facing side of the road.
From email: "One of my crew was partially buried in an avalanche today(head about 1’ down, leg and arm still above snow) at approximately 13:10 hrs. Slope was greater than 35 degrees, crown approximately 85 yards wide, over 3’ at its thickest point. I believe it was a NE exposure with wind loading at the top. I had a bad feeling about this slope and mentioned it to my crew and avoided riding on it until one rider ran out of gas and I had to help him. Upon completion of task, I rode back to a spot that wasn’t as safe a vantage point as what I had previously stayed at, but the intention w
From email: "One of my crew was partially buried in an avalanche today(head about 1’ down, leg and arm still above snow) at approximately 13:10 hrs. Slope was greater than 35 degrees, crown approximately 85 yards wide, over 3’ at its thickest point. I believe it was a NE exposure with wind loading at the top. I had a bad feeling about this slope and mentioned it to my crew and avoided riding on it until one rider ran out of gas and I had to help him. Upon completion of task, I rode back to a spot that wasn’t as safe a vantage point as what I had previously stayed at, but the intention w
Rider triggered Avalanche, 1 partially buried
From email: "One of my crew was partially buried in an avalanche today(head about 1’ down, leg and arm still above snow) at approximately 13:10 hrs. Slope was greater than 35 degrees, crown approximately 85 yards wide, over 3’ at its thickest point. I believe it was a NE exposure with wind loading at the top. I had a bad feeling about this slope and mentioned it to my crew and avoided riding on it until one rider ran out of gas and I had to help him. Upon completion of task, I rode back to a spot that wasn’t as safe a vantage point as what I had previously stayed at, but the intention was we were all on our way out. So I parked and within 30 seconds, I hear my friend yelling behind me. I turn and immediately think “oh he’s about to hit us”. So, I attempted to start up my sled, to no avail While watching behind me. Suddenly, a massive “snow cloud” appeared about 30 yards above him and it took about 2-4 seconds to register that it was an avalanche and not another rider careening out of control at us. By that time, it was too late to do anything. The avalanche had reached the back of my friend and my sled, pushing us forward about 6 feet at 3-4mph. After it stopped, I assessed 3 of four of our team was accounted for, and one (the one who yelled at us) was not. He was partially buried by the front of the avalanche much like our sleds were. Fortunately, within 5 seconds, I saw an arm and a leg sticking out of the snow and we had his airway and head cleared within about 20 seconds. He was located approximately 10 yards from us. "
Snowmobile triggered avalanche in Teepee Basin.
Forecast link: GNFAC Avalanche Forecast for Sat Feb 22, 2025
Snowmobile Triggered Avalanche and Partial Burial in Tepee Basin
Snowmobile triggered avalanche in Tepee Basin. One rider was caught, carried and partially buried. Visible arm and leg above snow allowed for successful partner rescue within 20 seconds of burial.
From email: "One of my crew was partially buried in an avalanche today(head about 1’ down, leg and arm still above snow) at approximately 13:10 hrs. Slope was greater than 35 degrees, crown approximately 85 yards wide, over 3’ at its thickest point. I believe it was a NE exposure with wind loading at the top. I had a bad feeling about this slope and mentioned it to my crew and avoided riding on it until one rider ran out of gas and I had to help him. Upon completion of task, I rode back to a spot that wasn’t as safe a vantage point as what I had previously stayed at, but the intention was we were all on our way out. So I parked and within 30 seconds, I hear my friend yelling behind me. I turn and immediately think “oh he’s about to hit us”. So, I attempted to start up my sled, to no avail While watching behind me. Suddenly, a massive “snow cloud” appeared about 30 yards above him and it took about 2-4 seconds to register that it was an avalanche and not another rider careening out of control at us. By that time, it was too late to do anything. The avalanche had reached the back of my friend and my sled, pushing us forward about 6 feet at 3-4mph. After it stopped, I assessed 3 of four of our team was accounted for, and one (the one who yelled at us) was not. He was partially buried by the front of the avalanche much like our sleds were. Fortunately, within 5 seconds, I saw an arm and a leg sticking out of the snow and we had his airway and head cleared within about 20 seconds. He was located approximately 10 yards from us. "
PWL and Wind Slab Avalanches in the S Madisons
We saw up to five recent avalanches from the last few days. 1-2 looked to have failed on PWLs, and the rest were wind slabs. Cornice collapses triggered at least two of these avalanches.
1. Cornice triggered wind slab in Sunlight Basin
2. Cornice triggered avalanche in Sage Creek
3. Likely PWL avalanche W of Kirkwood Ridge, lower in Cabin Creek
4. Older wind slab SW flank, Sage Peak
5. Likely PWL avalanche backside of Sage Peak