2008-2009 Colorado Snowpack Observations

**montanaskier** · 12-16-2007, 06:36 PM

So the wife and I just got back from our first real backcountry trip. We skinned up to the Sangree Frolicher hut outside of Leadville. This was a 3 day Avy 1 class thru 10th mountain. WOW, what a trip. I learned so much. As far as actual observations, I recoginze I am an Avy jong, but will post what we saw anyway.

We got some whoomping and cracking on slopes of 25 degrees and up that were east facing. We didn't see any natural avy activity or any real activity at all. Looked like right above the hut in the natural avy slide zone that the slope had ripped out and slid at some point, maybe a few days earlier. In our pit digging, at 12k or so, it was pretty variable depending on the aspect. Wind slabs were prevalent on all aspects, obviously much deeper on SE aspects. The compression tests we did yielded quite high scores and our R-block test was a 6. Looks like there was no snow at all on the ground before these last two storms, currently there is an average snow depth of around 3-4 feet. The bottom layer was quite faceted but mostly soft snow on top. Again, a great trip and hopefully the first of many.

**Rontele** · 12-17-2007, 09:45 PM

Back from Eiseman. Kind of a mixed bag regarding the snowpack. Sadly, there is a highly variable layer of facets deep in the pack. The layer is roughly 10 to 12 inches deep and sits below the five feet from the last two storms. The westerly aspects appear not to have as prevalent, this facet layer, resulting in a bomber snowpack.

Its going to be variable from slope to slope, aspect to aspect, and looks like we'll be dealing this for some time.

With new snow on the way through the end of the week, should see the danger in all zones rise.

Plus, the wind started blowing today.

**freejustin** · 12-17-2007, 10:37 PM

Sunday 12-16-07:

Jones Pass, below treeline. Still mininmal signs of instability. Some wind deposit soft slabs were building, and there were Q2 shears on NSF's just below the surface. But these were REALLY soft slabs. Might become a problem if we don't get more snow soon and the slabs harden.

Berthoud Pass, later that afternoon. Toured up past the WX station on the west side. Dug a pit above treeline on a S-SE slope. There were 3 distinct shear planes in the top 50cm or so. Mostly 4 finger slabs. The top layer failed while I was cutting out the back for a compression test. Not good, however the block didn't pop out completely (34 degree slope), so I gave it a Q2, borderline Q1. I was too cold to get out a lens, and the sun was receding, so I'm not sure what these slabs were failing on. I think they were small density changes, possibly several NSF events? Whatever they were, they were not easily detectable in the pit wall.

Meanwhile, I'm hearing other reports of a bomber snowpack in the central mountains. Depending on how things shake out, it seems like this could be a tricky winter in CO. Some places are setup with deep snow on the ground and minimal facets. Elsewhere, it sucks. But there's some fine skiing!

Cheers,
Justin

**Rontele** · 12-18-2007, 09:17 AM

Nice obvs, Justin. I agree that this is a season of a mixed bag, which will require extra caution.

**Deep Days** · 12-18-2007, 12:07 PM

12.16.07 Berthoud Pass

Excellent snow for skiing was to be had in the trees. I personally noted a tiny bit of surface instability in the trees of HHA/North Chutes and set off some 3-4 ft. cracks in a 3-inch deep soft slab on about a 35-degree pitch below tree line. The soft slab moved maybe 6 or 8 feet. Coverage was THIIIIN in the chute. We didn't get anything to move on the other side of the highway--towards Gaffney's playground, where we toured after the sun came out and it started to warm up.

Very light snow until 10:30 AM or so and relatively light winds below treeline, but it was consistently howling just past where the trees started to thin out. Much, much slabbier, hollower snow, with about a 4-inch windskin on top 100-ft above treeline. For safety's sake and for better skiing, I'd definitely recommend staying below treeline in the HHA area for now.

**~mikey b** · 12-19-2007, 07:35 AM

from the CAIC morning forecast....

http://avalanche.state.co.us/Forecasts/Vail+Summit+Co/

News of triggered avalanche activity continues to come in from the entire Summit County and Vail area zone. On Tuesday a skier triggered a good sized slab on a NE aspect just below treeline near Vail. The gentleman was carried by the slab, which failed about 20 feet above him, for about 800 feet. Escape routes were not present so he had no option but the ride which had him buried for most of the ride, but he popped out just as the slide was coming to a stop. This ride took him over at least one 15 foot cliff, but he ended up with only some impact bruises to his thigh, lost a ski, one pole, hat and goggles. Crown was 4 feet deep at the deepest, and about 60 feet wide. This was a wind slab created from recent moderate to sometimes strong westerly winds. A skier triggered a slide on the Little Professor slide path on Monday too. The slide initiated on a wind loaded south aspect just below the ridge, cracking 1 to 2 feet deep. Winds have blown from the northeast, north, west, and southwest. Observers note lots of complex wind loading and some cornice collapse at ridgelines. West slopes are largely stripped while wind slabs, sensitive drifts, and cross loaded terrain features pepper most other aspects on higher elevation slopes as well as on exposed areas below treeline. Fresh slabs can be reactive on steep slopes where they are sitting on low-density recycled powder. Observers on Monday noted that fresh wind slabs 20-30cm deep are not bonding well with the underlying wind slab. Strong winds have drifted snow well down on slopes and into start zones. This means you may get lured farther down a slope as the slab thickness demonstrates strength.

**homerjay** · 12-19-2007, 11:45 AM

^^ that slide was in Old Man's, fyi.

**MakersTeleMark** · 12-19-2007, 12:44 PM

Originally Posted by homerjay

^^ that slide was in Old Man's, fyi.

Thanks, I was going to call them and ask where exactly. What part do you know?

12.16.07 - N. of Vail

Dug a pit on a 30 deg slope 11.5k west facing. 5.5 ft of solid snow, mostly windloaded, 1 full ft. depth hoar to ground (grass still green under there). While I was in the pit, a partner jumped on his pit nearby and the whole slope boomed and settled. I dropped a good foot and a half. Decided not to ski the slope (38 deg or so) even though I really thought the big pack could bridge the hoar, but if it did rip, it would have been a big one. Skied slopes with less/no loading.

**~mikey b** · 12-19-2007, 07:59 PM

not familiar enough with Vail - where is Old Man's?

**MakersTeleMark** · 12-20-2007, 02:19 PM

**~mikey b** · 12-20-2007, 08:07 PM

got it - thanks christian

**couloirman** · 12-22-2007, 03:19 PM

careful out there maggots. At berthoud on N -> E aspects my group got a couple soft slabs to run, each going approx 100-200 yards. None of them were large enough to bury you, but one of them happened over cliff bands and would have been a scary ride had it fractured above us. They each ran on a layer of sugar snow and had crowns from 8-18 inches tall.

EDIT: I didn't have my altimeter with me, but it was only about 500 feet above the BP parking lot(you could actually see the debris from one of them from the parking lot, right through the lookers right side of the huge cliff bands across the highway), so it did not occur very high... Dig pits, and be wary...

**freejustin** · 12-22-2007, 03:22 PM

Originally Posted by couloirman

careful out there maggots. At berthoud on N -> E aspects my group got a couple soft slabs to run, each going approx 100-200 yards. None of them were large enough to bury you, but one of them happened over cliff bands and would have been a scary ride had it fractured above us. They each ran on a layer of sugar snow and had crowns from 8-18 inches tall. Dig pits, and be wary...

What elevation was this?

**Rontele** · 12-23-2007, 05:51 PM

Just returned from a Front Range tour near Allenspark. The wind was howling hard and blowing the NW aspects nearly clean. This has added a further variable to an already variable snowpack as there are numerous drifts and hardslabs depending on terrain and trees, etc.

I did notice that the new windslab was not bonding well to the old snow surface. The slabs were shallow, but with still alot of snow to transport, I'd expect them to grow.

Finally, like the CAIC has been reporting, these new slabs are forming lower down on the slopes than you'd usually think. Be extra careful.

Oh yeah, the skiing conditions in the protected trees were $$$$

**GoldenBear** · 12-26-2007, 10:37 PM

Just got back from Berthoud. The snow in the trees was $$ but above tree line it was a little sketchy. As we skinned below the ridge, the snow was whoomphing and cracking.

The Cornice we approached:

Before we even dug a pit we realized that the snow on the surface was incredibly slabby. We dug our pit on a SE facing slope at just under 30 degrees. Once we got into our pit a bit more we found the following:

20cm of wind slab on the surface

Our pit was about 5 feet deep. We did our sheer tests and checked out the different layers. I didn't get any good photos of this since my camera is temperamental and I suck at using it. But once we loaded the uphill portion of the pit, the snow collapsed about 75cm deep and in a very slabby manner.

As soon as the deep collapse happened, we turned around and headed back for low angle trees. It was awful to leave such a nice line untouched but It is better than being dead. Some people had the ca hones' to ski some 30-35 degree pitches today. I wasn't one of them. Caution was on my mind today.

**~mikey b** · 12-27-2007, 10:45 PM

I'm new here. I don't really know shit about this snowpack other than what I've seen in the last year. I got here late last season, and a lot of snow was already on the ground. This year, I've been looking at it and poking around in it since the first flakes.

I just read and wanted to share Lou Dawson's opinion about and approach to this season's early snowpack.

http://www.wildsnow.com/

I can’t write enough about how impressed I am with our snowpack. November scared me, as it looked like the early season snow we slogged during our elk hunt was turning to sugar that would eventually try to support a slab — and of course fail into deadly snow slides (as is happening in Utah and Montana). We’ve still got a bit of that condition up above timberline, but much of the early sugar snow got burned off or matted down before we started our huge series of December dumps.

Now, as shown in the photo (below), in many areas we have a six to eight foot snowpack that’s nearly solid marble from the top to the ground. It’s almost surreal having a snowpack this good in Colorado. It kind of throws you off. You know you can go more places and do more things, but years of caution habits are hard to reconcile. My take: stick with the program, use the good habits, only creep up to the edge a bit closer. So that’s what we did, and it was good.

I like the advice --> stick with the program - use good habits

**freejustin** · 12-28-2007, 12:20 AM

Yeah, Mike, we're in a pretty amazing pattern here. And while it has built a solid pack in places, lurking deep slab instabilities are creeping me out right now. I think it's still really spotty. Those who have been getting out regularly since November 1 probably have the best feel for localized areas. I haven't been in the central mountains at all, but I hear things are stable there. Front Range where I'm at it seems to really vary.

Anyway, +1 to sticking with the program (and staying warm tomorrow! Yikes!)

**pde20** · 12-28-2007, 12:56 AM

Originally Posted by telemike

I'm new here. I don't really know shit about this snowpack other than what I've seen in the last year. I got here late last season, and a lot of snow was already on the ground. This year, I've been looking at it and poking around in it since the first flakes.

I just read and wanted to share Lou Dawson's opinion about and approach to this season's early snowpack.

http://www.wildsnow.com/

I can’t write enough about how impressed I am with our snowpack. November scared me, as it looked like the early season snow we slogged during our elk hunt was turning to sugar that would eventually try to support a slab — and of course fail into deadly snow slides (as is happening in Utah and Montana). We’ve still got a bit of that condition up above timberline, but much of the early sugar snow got burned off or matted down before we started our huge series of December dumps.

Now, as shown in the photo (below), in many areas we have a six to eight foot snowpack that’s nearly solid marble from the top to the ground. It’s almost surreal having a snowpack this good in Colorado. It kind of throws you off. You know you can go more places and do more things, but years of caution habits are hard to reconcile. My take: stick with the program, use the good habits, only creep up to the edge a bit closer. So that’s what we did, and it was good.

I like the advice --> stick with the program - use good habits

I second justin's sentiment above. While I agree with "stick w/ the program, use good habits," you've gotta keep in mind that Dawson is primarily a Roaring Fork Valley guy and that weather patterns have been very different for different parts and ranges of Colorado. In my limited action touring on the Front Range this thus far this year, the situation in the Elks or even San Juans is NOT what we have going on around here. I'm certainly jealous that I don't have the opportunity to be partaking in what a much more experienced individual like Dawson thinks is an epicly stable snowpack in that part of the state, maybe that is good motivation to get my ass out there!

**Rontele** · 12-28-2007, 08:01 AM

I third the sentiments above. If you think about it, the Ellks or West Elks (that photo easily could be from Coal Creek Basin outside of Redstone or Marble), got roughly 95% of their existing snowpack from the early december dumpage (remember some of the Aspen TRs?)

OTOH, in the front range we have a VARIABLE layer of facets and a lot more wind to add to our mixed bag snowpack. As evidence of the variability, the CAIC forecast yesterday told of 20-24 inch layer of facets on South Diamond peak near Cameron Pass. BUT if you look at the first page of the Ski Forum, WYSPLITRIDE has a TR from that same peak that looks fairly bomber.

And I bet our snowpack is different than what you're experiencing up on VP.

**freejustin** · 12-28-2007, 08:16 PM

12-28-07 Berthoud Pass

Okay, so something of interest on my afternoon tour...

I rolled into the Berthoud Pass parking lot around 1ish, parked in the lot so that I was facing the steep east facing terrain that's right above the road. Looked up, saw a skier just lookers right of the cliffs, then saw an avalanche!

That woke me up. I saw him ski down, so everything seemed fine.

Anyway, I went poking to see why that spot had run, while everything else had been skied with no action. Since I was alone, I didn't go check out the fracture (really tempted to go back tomorrow) but standing in the debris, the FX looked about 50cm deep and 50 feet wide. What was interesting, however, was that I could see rocks and branches poking through the bed surface. Looks like it might have effectively run to the ground.

So, without any real empirical evidence, my thought is that this skier hit a steep, shallow spot. The super cold temps have put the facet factory in overdrive the past couple of days, and stressed the snowpack. I wonder if we'll see more stuff slide this weekend due to rapid faceting and more winds? I'm thinking both facets near the ground in shallow spots, and shallower slabs on top where NSF are movin' and groovin'.

Also, I dug a quick pit on the ridge above where the slide occurred. The snow was much deeper here, however I got a slightly reactive NSF layer about 25cm down. The temperature gradient was almost 3 degrees C/10cm in the top 25cm layer around 2PM. So keep in mind, things are going to be changing, and fast.

I should also mention this slide = terrain trap. Went over a cliff and into trees. Be safe this weekend!

**Rontele** · 12-29-2007, 11:54 AM

Justin,

The CAIC report did indicate that it ran to the ground. These cold temps are making riding conditions difficult and like you said, putting the facet factory on full bore.

I am actually looking forward to some warm temps and high pressure for a good chunk of next week before the next storm cycle (starting next weekend)

**freejustin** · 12-29-2007, 04:00 PM

Originally Posted by Rontele

Justin,

The CAIC report did indicate that it ran to the ground.

That was my report, actually... Maybe the skier who triggered it also reported? Dunno...

**Hacksaw** · 12-29-2007, 04:05 PM

Good to see someone from the CAIC is checking in here. Because I didn't send them that report.

**freejustin** · 12-29-2007, 04:12 PM

errr... I meant I'm the one who emailed the CAIC about the slide.

Anyway, Hacksaw, do you have a sense for how many non-observer reports the CAIC receives? Just curious how well the general public does with emailing in info and obs.

Justin

**freejustin** · 12-29-2007, 04:31 PM

Butler Gulch 12-29-07

Now, for something completely different from yesterday. In line with the CAIC's observer a day or two ago, I saw bottomless facets down in the trees and near the parking lot.

We toured up and skied the NNW facing shots below that big saddle. Lots of blowing snow and wind. Conditions were REALLY variable. It was quite soft, and actually great skiing. We were really careful with terrain selection, however. I stomped on a mini slope at about 11,800 and got a 20 foot wide fracture, and the slab ran about 5 feet with me on top.

Anyway, two distinct slabs actually broke. The top slab was 10cm of recent wind deposit. Below that was a harder slab, about 10-15cm deep. Bed surface was a thin layer of NSF (recent cold temps!). Compression test yielded a CT 1 Q1.

The moral of the story was that we skied windward sides of the gullies. Here there was no recent loading, no cracking or movement, and much more stable snow. Soft slabs on top of facets, basically. Down in the trees it was knee deep and lovely. Front range definitely a mixed bag.

J