Snow Observations List

Centennial Range
Centennials - Montana
Mt. Jefferson
Incident details include images

We rode around most of the Jefferson area. The area is covered in tracks wall to wall. Reminded me of Teepee basin after a holiday weekend. It was hard to find untracked snow. Really hard. Winds have blown but just didn't have much snow to move. We rode in a lot of avalanche terrain and even climbed several steep chutes. 

Notice a weak layer that produced ECTP15. I saw no signs of this layer in crossing test slopes or riding above another sidehill track
We triggered one wind slab about 10 ft wide and 4-8 inches deep. 
 
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Centennial Range
Centennials - Montana
Hellroaring yurt, centennial range

we observed approximately 20 inches of new snow from the storm Wednesday 2/5 to Sat 2/8 morning. The storm ended very warm, even with about 10 minutes of rain Sat morning. This formed a thin breakable rain crust up to 9,000 feet. Over the day Saturday, we received an additional 2 inches of low density snow and heavy wind from the NW as a cold front passed. Sunday was clear, calm, cold, but by mid day had warmed south facing slopes to the point of wet roller balls. The only natural slide observed was in the buffalo hump area on a NE facing slope below a cliff band. It looked to be 2 feet deep, 200 feet wide.

Pit data:

On Sunday morning, pit dug on a SE facing slope 8400 feet. 152cm snowpack. ECT 13 broke at 125 cm, Quality 2. This broke on a rain/sun crust. Facets 0-30cm. The crust formed Saturday morning was prevelant and would be of concern after an additional load.

Pit on N facing aspect at 7800 feet showed 180cm depth and stable. Conducted CT and shovel shear with no results. However, Crust from Sat morning rain was evident and could be of concern after additional load.

We found the best conditions to be in protected bowls on West to North to East aspects.

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Centennial Range
Centennials - Montana
Hellroaring
Incident details include images

Spent the afternoon in Hellroaring drainage trekking to the hut. Around 2:30 the clouds cleared allowing us to view higher peaks and bowls. Did not observe any crown lines on steep cut banks above the creek, or higher up. Expected to hear and see more signs of instability, but did not. Suprisingly little wind and drifting during the last storm, 18-24" consolidated new snow in the last 2 weeks as evidenced by accumulation on the hut. Snow depth at 7500' in a SW facing meadow was 150 cm. Fairly close to what the White Elephant Snotel reports just a few miles away. Didn't have time to do pit tests since I was dropping a group off and my dog ruins any sense of an "undisturbed column", however in general this new snow apprears to have developed into a very dense and stiff slab 18-25" everywhere likely hiding the lurking dragon in low angle terrain we stayed in during our approach.

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Centennial Range
Hellroaring Creek
Tin Cup Pass-Mt. Jefferson-Centennials

Aspect: north
Slope: 30
HS: 160cm
Basic snow structure: round 160cm-50cm rounds, 50-40cm facets, 40-0cm large facets.
ECTX
CT13 at 40cm not planar

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Centennial Range
Reas Peak
Read Peak, Centenials -Island Park, ID
Incident details include images

Pictures sent to me from an out of state friend. No other info at this time other than that he was able to ride through it uphill.

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Centennial Range
Centennials - Montana
Hellroaring Drainage
Incident details include images

During a 3+ mile tour from 6500' to 8500' we did not witness any old or recent avalanche activity on upper elevation slopes, or low elevation areas such as steep banks leading to the Hellroaring Creek where we have in previous season, that isn't to say that high winds haven't filled any observable crown lines in. The snow depth in this region was surprisingly shallow given the reported snow depths at reporting snotel stations. i.e., White Elephant Snotel. It seems as though high wind has scoured exposed areas including ridge tops West facing slopes heavily. Between 7,500' & 8,300', all NW-SW aspects had roughly 65cm of unconsolidated snow. The lower half of the snow pack consisted of various sized facets depending on aspect. In general, we observed a snowpack with poor structure and fair strength. Pit results did not yield propagation in any layers. Compressions tests showed low quality shearing at the interface between the new snow and the older faceted layers.

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Centennial Range
Two Top
Centennial Range and Two Top

As you're well aware, the snowpack around West is crap. We found conditions on Two Top to be very similar to Lionhead. We didn't see any avalanche activity but did get some large collapses and unstable test results. Surprisingly, conditions were quite different in the Centennials. We rode on the west side of the range and found 30-50 cm's of snow on south and west-facing slopes. These aspects lacked weak layers near the ground and had a relatively shallow but stable snowpack. As we ventured onto shadier slopes (north-east) we found a different structure. Snow from early in the season had faceted and was capped by a 30-50 cm slab. In general, the snowpack in Centennials is better than Lionhead and Two Top.

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