24-25

GNFAC Avalanche Forecast for Sat Feb 1, 2025

Snowpack and Avalanche Discussion

<p><span><span><span><strong><span><span>Wind Slab avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> on wind loaded slopes are the primary concern today. A foot of new snow and perfect drifting winds means these drifts of new snow could easily be 2-4 ft deep.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The new snow is piling up on a variety of snow surfaces - some weak, some not - so check to see how well the new snow has bonded to the old snow surface before getting onto slopes steeper than 30 degrees (</span></span></span></span></span></span><a href="https://www.youtube.com/watch?v=1zbdABx9LzE"><span><span><span><strong>…;). Conditions could be quite touchy on slopes with weak snow underneath the fresh drifts.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The low density snow is unlikely to form much of a slab without wind effect, but remarkably soft slabs can break if they’re sitting on surface hoar (a weak layer which we’ve had reports of&nbsp; - </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33903"><span><span><span><span><span><…;), so don’t entirely let your guard down on non-windloaded slopes.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Human triggered avalanches are likely and the avalanche danger is CONSIDERABLE on wind-loaded slopes. On all other slopes, the avalanche danger is MODERATE.</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 also the primary concern in the Madison and Gallatin Ranges, Lionhead area, and mountains around Island Park. Fresh wind slabs were already breaking yesterday, before it started snowing (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33925"><span><span><span><strong><span…. Blackmore observation</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>). Expect more of the same today, but they could be both deeper and wider. The deeper the drifts of new snow, the more dangerous conditions will be. A short, intense period of snowfall this afternoon may rapidly form new, unstable drifts.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Weak snow has been reported on the old snow surface across the area (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33900"><span><span><span><span><span><…;, </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33895"><span><span><span><span><span><…;). High winds may have blown away some of that weak snow before the new snow started falling, but probably not all of it. So if you find a wind drift more than around 6” deep, check to see what it’s sitting on top of. Cracks shooting out in front of you are bullseye data that you’ve found an unstable drift.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Human triggered avalanches are possible and the avalanche danger is MODERATE.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>A dusting of new snow in the Bridger Range won’t do much to increase the hazard today. Watch out for thin drifts of new snow if you’re riding in terrain where even a small slide would have big consequences (above rocks, cliffs, etc.) and stick with good travel practices (wearing rescue gear, having a partner watching from a safe spot) in case you get unlucky and manage to trigger a bigger slide in an older winddrift.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Conditions are generally safe and the avalanche danger is LOW.</span></span></span></span></span></span></p>

KING AND QUEEN OF THE RIDGE

Join us for the King & Queen of the Ridge TODAY at Bridger Bowl! Registration for the event has closed, but come join us at the top of the Bridger lift to cheer on the participants!

Small windslabs on Mt. Blackmore

Mt Blackmore
Northern Gallatin
Code
HS-N-R1-D1
Latitude
45.44440
Longitude
-111.00400
Notes

Three small fresh natural wind slab avalanches were seen on the east face of Mt. Blackmore on 1/31/25.

Number of slides
3
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
1
D size
1
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

From obs: "Wind was rocking in alpine today, fresh windslabs forming and naturally releasing. I could make out 3 on E face, but rough vis with blowing snow. Exposed terrain in alpine had about .5” ice crust from yesterday’s sunshine.

This slab (in pic) released around 11-noon-ish." Photo taken 1/31/25

Northern Gallatin, 2025-02-01

Windslabs on Blackmore

Date
Activity
Snowboarding

Wind was rocking in alpine today, fresh windslabs forming and naturally releasing. I could make out 3 on E face, but rough vis with blowing snow. Exposed terrain in alpine had about .5” ice crust from yesterday’s sunshine.

This slab (in pic) released around 11-noon-ish. 

Region
Northern Gallatin
Location (from list)
Mt Blackmore

Surface Hoar, Sugar Snow

Date
Activity
Skiing

Toured out of Pine Creek yesterday and up to around 9000ft. We found large surface hoar crystals around the creek and smaller NSF in most covered areas. In steeper, north-facing terrain, we found a fairly uniform snowpack in areas that had been seeing some wind and surprisingly good surface conditions for skiing. We found a few feet of sugar snow near the ridge line with large faceted crystals lower in the snowpack, restricted to mostly sheltered areas. While traveling, we saw no signs of instability except some wet slides from the past few warm days. However, the snowpack around Pine Creek is much thinner than the rest of the forecast area and is showing significantly more signs of faceting, especially in sheltered areas.

Region
Out of Advisory Area
Location (from list)
Pine Creek
Observer Name
Jay Alford

GNFAC Avalanche Forecast for Fri Jan 31, 2025

Snowpack and Avalanche Discussion

<p><span><span><span><span><span><span>Avalanche conditions are generally safe today. Still, there are some things to watch out for.&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>The first thing to watch out for is old wind drifts. Mostly these will be well bonded after a week of warm temperatures, but be alert in case you find someplace where they aren’t. A report yesterday of a recent </span></span></span></span></span></span><span><span><span><strong><span><span>Wind Slab avalanche</span></span></strong></span></span></span><span><span><span><span><span><span> on Woodward Mtn. that broke 1-2 ft deep and 250 ft wide shows that we can’t totally write off the possibility of triggering one of these slides (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/33914"><span><span><span><span><span><…;).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Wet snow concerns will be minimal today with generally a good refreeze overnight and clouds keeping melting in check today. But, there are places where the air temperatures stayed above freezing overnight so watch out for </span></span></span></span></span></span><span><span><span><strong><span><span>Wet Loose avalanches</span></span></strong></span></span></span><span><span><span><span><span><span> if you find a snowpack that hasn’t entirely refrozen (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/images/25/point-release-avalanche-south-slo… of Wet Looses yesterday</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>).</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>Snowfall will begin this afternoon. We don’t expect much to accumulate before nightfall, but if it comes in early and heavier than expected - watch out for newly forming drifts. The new snow will fall onto a variety of old snow surfaces, including some very weak snow, so even thin drifts may be quite reactive (</span></span></span></span></span></span><a href="https://youtu.be/SqfcVtQ4uxY?feature=shared"><span><span><span><span><s… video</span></span></u></span></span></span></span></span></a><span><span><span><span><span><span>).&nbsp;</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>With snow and strong winds expected through the weekend and into next week, expect the avalanche danger to rise. The more it snows and blows, the more rapidly the danger will rise.</span></span></span></span></span></span></p>

<p><span><span><span><span><span><span>For today, the avalanche danger is LOW.</span></span></span></span></span></span></p>

KING AND QUEEN OF THE RIDGE

Join us for the King & Queen of the Ridge this Saturday at Bridger Bowl! Hike, ride and help us raise money. It’s a blast! Fundraising prizes for the top 5 individuals who raise over $500. No racing is necessary to compete for the fundraising prizes.

Wind Slab avalanche on Woodward Mtn.

Taylor Fork
Southern Madison
Code
HS-N-R2-D2
Aspect
NE
Latitude
45.06070
Longitude
-111.27200
Notes

Wind slab avalanche on Woodward Mountain, observed on 1/30. Avalanche appeared recent but date of slide is estimated.

From email: "Today I drove down Taylor fork road, with the thought of potentially getting up on woodward mtn, until I saw a crown on the NE
Face of its northern summit, basically wall to wall near the top of  the slide path. There were a couple other sled tracks that also went to the end of the road, so I figured maybe it was pretty recent, as I didn’t hear about it in the advisory. Concerning because it appears to have propagated maybe 250ft across,  while maybe only 1-2 ft deep" 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Slab Thickness
18.0 inches
Slab Width
250.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

From email: "Today I drove down Taylor fork road, with the thought of potentially getting up on woodward mtn, until I saw a crown on the NE
Face of its northern summit, basically wall to wall near the top of  the slide path. There were a couple other sled tracks that also went to the end of the road, so I figured maybe it was pretty recent, as I didn’t hear about it in the advisory. Concerning because it appears to have propagated maybe 250ft across,  while maybe only 1-2 ft deep". Photo taken on 1/30/25. Photo: T. Grande

Southern Madison, 2025-01-31