Was climbing up a steeper area on the east side of Reas peak. Near the 2/3 point up the hill I watched a large crack suddenly open up 1-2" wide in the snow and I crossed over it. The slab did not slide. The depth or total length of the crack is unknown.
Rode in to put up the Taylor Fork weather station on Pika Point. Coverage on the road down low is thin, but just barely doable.
Dug a pit on an E aspect in Sunlight Basin at ~9500 ft. The entire two foot deep snowpack was weak and faceted. Even the new snow that fell last weekend is beginning to facet and surface hoar is growing on top. The slab has broken down enough that we couldn't get it propagate in an ECT (ECTN17 & ECTX) and the slab fractured in a PST (PST15/100 SF). We also dug a quick pit on the headwall in Carrot Basin and found a similarly weak ~2ft deep snowpack.
The chief concern right now would be finding a spot that does have an intact slab, most likely in a windloaded area.
Ian Hoyer puts up the weather station in Taylor Fork. Photo: GNFAC
Ian Hoyer stands in a 60 cm deep snowpit near Sunlight Basin, Taylor Fork. Photo: GNFAC
<p><span><span><span><span><span><span>Signs of instability are sprinkled around our forecast area. Yesterday a skier got collapsing and cracking on the </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29693"><span><span><span><strong><span… Basin</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span> divide. On Christmas day a skier triggered large </span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29690"><span><span><span><strong><span… at Lionhead</span></span></u></span></strong></span></span></span></a><span><span><span><span><span><span>, the day after Alex and I found instability in our snowpits (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29674"><span><span><span><strong><span…;) and Dave triggered a small wind-load in the Bridger Range (</span></span></span></span></span></span><a href="https://www.mtavalanche.com/node/29673"><span><span><span><strong><span…;). These red flags warn us that not all slopes are stable. We have many layers of weak snow (surface hoar, facets, depth hoar), yet the exact type doesn’t matter. Big Sky Snow Safety succinctly wrote, "...every interface is characterized by weakness." </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>All slopes have weak snow, yet only some are unstable, which presents a conundrum. We must determine which is dangerous and which is not. Slopes under 30 degrees steepness are generally safe because they are not avalanche terrain. If you are looking to play on steeper slopes, dig and test layers or be content rolling the dice. A clean break in a column test indicates unstable conditions.</span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>Triggering an avalanche 1-2 feet deep is possible, especially on slopes with a cap of dense wind slab. Without a whumpf or cracking, the avalanche risk is not obvious and you will have to put your shovel in the snow to assess stability. </span></span></span></span></span></span></p>
<p><span><span><span><span><span><span>For today, the avalanche danger is rated MODERATE on all slopes in our forecast area. </span></span></span></span></span></span></p>
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar.
I toured up the private property line to the ridge between Beehive and Bear Basin, I skied partway down into Bear Basin from where the prayer flags used to be. I was breaking trail back up and Clyde (dog) was wallowing in the facets so I gave a big jump to try to pack in the skin track better for him and got a nice whumph, cracks shooting out about 10'. Some slopes had fresher snow forming a slab over facets, some slopes had more facets than slab, the west side going back into Beehive had a stout melt freeze crust underneath a few inches of snow. I didn't go looking for buried surface hoar so I can neither confirm or deny its existence.
I toured up the private property line to the ridge between Beehive and Bear Basin, I skied partway down into Bear Basin from where the prayer flags used to be. I was breaking trail back up and Clyde (dog) was wallowing in the facets so I gave a big jump to try to pack in the skin track better for him and got a nice whumph, cracks shooting out about 10'. Some slopes had fresher snow forming a slab over facets, some slopes had more facets than slab, the west side going back into Beehive had a stout melt freeze crust underneath a few inches of snow. I didn't go looking for buried surface hoar so I can neither confirm or deny its existence.
Skiers experienced cracking and collapsing on Lionhead Ridge on Monday, Dec. 25th while breaking trail on the NE side of the ridge.
