Tahoe Weather, Conditions, Stoke, and What's Up Thread...

[harpo-the-skier]

Any updates on the casualties from yesterday? I know the guy from Donner didn't make it, but I was wondering how the others were doing.

[splat]

Just got a call from TeleRob, who does the a/c on hiway 88. Carson Pass/88 is not exempt from the layering/triggering whatsoever. He said the key thing here is that the early December rain has created a persistent layer of icy crust that releases every time new snow lands on it, so it's not like its going to be safe after everything slides and new snow falls. Unless significant warming occurs that will consolidate it. When things slow down, I'm hoping to go on a midnite bomb run with him.

Be safe out there.

[skinnyskier]

Just got a call from TeleRob, who does the a/c on hiway 88. Carson Pass/88 is not exempt from the layering/triggering whatsoever. He said the key thing here is that the early December rain has created a persistent layer of icy crust that releases every time new snow lands on it, so it's not like its going to be safe after everything slides and new snow falls. Unless significant warming occurs that will consolidate it. When things slow down, I'm hoping to go on a midnite bomb run with him.

Be safe out there.

Putting the persistent in persistent buried weak layer...

[SchralphMacchio]

Feels more like a PNW snowpack than Tahoe snowpack so far this season ...

[Driver]

Suddenly not much complaining about terrain being not being open.

I agree w Splat and think this rain crust stays with us in a dangerous way for quite some time. The more snow loaded on top the greater the consequences

[SchralphMacchio]

Round 3 just started up at Luther Pass. Not "dumping," but small dendrite snow coming down at a decent rate.

Moderate wind gusts.

[powdork]

Suddenly not much complaining about terrain being not being open.

I agree w Splat and think this rain crust stays with us in a dangerous way for quite some time. The more snow loaded on top the greater the consequences

but the places where it doesn't slide it will and in many cases has been bridged. kind of why i was wondering if places that haven't been controlled are safer now only as it relates to the rain crust

[splat]

but the places where it doesn't slide it will and in many cases has been bridged. kind of why i was wondering if places that haven't been controlled are safer now only as it relates to the rain crust

Not on the north aspects, for sure.
Problem is, anywhere else, it only takes a little weight to find out.
If it doesn't warm to bond, it could decide to go sometime today or sometime in March.

[powdork]

That's exactly what has happened in a few zones. Before this last cycle lots of things including that area above the fingers had slid off the rain layer. The area the patroller was involved in yesterday at alpine had not yet been opened for the year so it was very much a 'natural' condition. There was a pretty big section of beaver bowl at alpine that slid last week and you could literally see runnels on the bed surface. You guys were getting more snow than us down there but dust on crust was a regular phenomenon with all that light poofy stuff that was falling previously. Before that, the entirety of squaw and alpine were glazed over boiler plate.

was talking with a bud on the skin track today and mentioned specifically the difference in the way that storm ended. there was a few inches of snow at kirkwood and carson pass, but not much anywhere else. it definitely was not boilerplate (pics from after the rains). i was pointing out that only the most wind exposed ridges and prominent rock were boilerplate. that didn't seem to be the case up north.

[kidwoo]

was talking with a bud on the skin track today and mentioned specifically the difference in the way that storm ended. there was a few inches of snow at kirkwood and carson pass, but not much anywhere else. it definitely was not boilerplate (pics from after the rains). i was pointing out that only the most wind exposed ridges and prominent rock were boilerplate. that didn't seem to be the case up north.

Yeah I was looking at all your and some other peoples' pics and what you guys were saying........it was definitely a little different up here, which is why I said "up here". I meant north lake, not up in tahoe in general.....sorry if that wasn't clear. I haven't been south of Jake's yet this year but you guys certainly got different amounts and kinds of snow for a while. Most of the ski areas here were literally a sheet of ice for a while. It was gross. See earlier posts in this thread about south faces (one side of beaver bowl, idiot's etc....) softening up. That's all that ever changed before it got (really) cold and snowed.

[onehotchili]

rip bill

[powdork]

fuck!
never sounded good but still was hoping.

[snapt]

Vibes to the Alpine team, thanks for all the work you do.
http://www.kcra.com/news/local-news/...3/-/index.html

[jables]

Two tough days for the Alpine community. Wanted to talk to each member of patrol I saw and thank them and send my condolences, but I didn't. I think I was worried about bringing it up, because I knew it was on all of their minds.

Sherwood was spinning today, but when I left around 11 it wasn't loading. Heard lots of folks saying they were hoping it would open, but I figured it wouldn't. Doubt it did (although I'm sure if it did, someone will let me know).

Did my few laps this morning on groomers, all of the snow pack talk fresh in my mind. Serious stuff. I sure hope people are aware of what is going on. I've been fearing bad news from areas just outside Alpine's "gates" for some years now. Let's hope those fears just linger, and don't become reality.

On lighter news, snowing pretty well at my place up in Talmont. Christmas dinner is coming together and the bourbon is delicious. Merry Christmas to all.

[Truckee Joe]

Rip Bill Foster and condolences to all patrollers in the Tahoe area. These are the worst conditions to have to work in and I thank you for risking everything.

[lepistoir]

Feels more like a PNW snowpack than Tahoe snowpack so far this season ...

Interesting perspective considering it was Colorado-like weather that took that layer and faceted it after the coastal snowpack got all rained on

[Ottime]

but the places where it doesn't slide it will and in many cases has been bridged. kind of why i was wondering if places that haven't been controlled are safer now only as it relates to the rain crust

This. Even with a PWL, as snow depth piles up, it becomes harder and harder to trigger. After a few meters, it takes a fair amount of weight to penetrate. Does not make things safe, by any means. As the pack melts in spring, we could see sliding on this layer, if it buried enough. Best case scenario is we get a significant thaw before then, water percolates through the pack, and we get a referee that bonds the layer.

From what I saw around KW, the ice layer was topped/finished with a little snow. Perhaps that issuing the difference. Still, and interesting year for Tahoe snowpack, to say the least.

I would be interested to see what Schralph and Harpo find at Luther. A bit of put digging may be in my future. PD, where did you skin and what did you observe today?

[powdork]

Best case scenario is we get a significant thaw before then, water percolates through the pack, and we get a referee that bonds the layer.

i just hope they get their contract negotiations settled in time. the replacement refs suck!

[davieboot]

Sad sad news about Bill. Working so hard, life on the line, just so we can have fun. Thank your patrollers.

[SchralphMacchio]

Condolences to F&F of Bill
May he and Andrew have never ending taps of cold beers and free flowing turns for eternity.

Interesting perspective considering it was Colorado-like weather that took that layer and faceted it after the coastal snowpack got all rained on

From what I've learned over recent years just reading the Whistler/PNW threads, this seems to be a classic PWL setup in that region ... they get drastic temp swings in precip due to low elevation but higher latitude. So you'll get rain that refreezes to a sheer ice lens, and then either a poor bond of the next snow layer, or worse, near-surface faceting due to the extreme temperature and vapor pressure gradients caused by significant cold. From my recollection, the really, really big significant slides up at Baker resort (12 to 20 foot crown heights) and Whistler resort that I've read about in recent years have been set up on pineapple express raincrusts and then near surface faceting of the next snow layer during cold spells. The thing with near surface faceting is that you are effectively working with a snowpack depth of the snow layer on top of the crust, because the local gradients and vapor pressure differentials are what drive vapor transport (faceting). So when the temperature swings with a fat ice lens in the snow pack, you can't simply say "it's 7 feet of snow on the ground, it's got a mellow gradient compared to Colorado." This is exactly what drives the problem with "dust on crust," and then cold, that Woo was complaining about this morning.

I've only been paying attention to CA snow conditions for the last 5 years, but I don't get the sense that we get significant rain events on top of snow nearly as much as the PNW ... I feel like most of the high elevation rain in the Sierra trends in October or May, before we have an established pack or well into the spring melt-freeze or just melt time of year. It usually seems like once the snow pack gets established, we typically avoid significant rain to create a high-heat capacity ice layer above treeline. I know we've gotten near surface faceting on top of M/F and sun crusts before (the very sad Chris Trethaway slide setup a few years back), but it seems to me like with those types of crusts there is a different bonding interface and possibly less heat capacity (due to less water content in the ice/crust layer) at work to create season-long PWLs - but I haven't read any research or papers indicating that to be fact, just my conjecture. Additionally, we get a lot more sun than the PNW which brings temps back up and promotes re-rounding of these types of facets.

Please feel free to call me out on any of this if you know otherwise people. The whole point of this discussion is to keep everyone safe and educated, and I'm up for being schooled myself.

This. Even with a PWL, as snow depth piles up, it becomes harder and harder to trigger. After a few meters, it takes a fair amount of weight to penetrate. Does not make things safe, by any means. As the pack melts in spring, we could see sliding on this layer, if it buried enough. Best case scenario is we get a significant thaw before then, water percolates through the pack, and we get a referee that bonds the layer.

From what I saw around KW, the ice layer was topped/finished with a little snow. Perhaps that issuing the difference. Still, and interesting year for Tahoe snowpack, to say the least.

I would be interested to see what Schralph and Harpo find at Luther. A bit of put digging may be in my future. PD, where did you skin and what did you observe today?

Remember that before we got the St. Paddy's day storm cycle and then before and after the April Fools storm cycle - the temperatures in March/April were very warm to consolidate/heat the late Feb snow. The facets did eventually start rounding on various aspects throughout March and April so we never saw those huge 5+ foot crowns later in the year that we feared ... so after this current Xmas cycle is through, I am actually looking forward to Juneuary on a really fat snowpack of >50% seasonal avg at upper elevations! May (the verb, not the month) 2013 be a time of healing!

For our findings today ... Harpo and I only went right off the road due to time constraints so our pit was at 7700'. Not really relevant for judging safe skiing conditions, but more to practice doing snow tests and see what's going on down low. We found that I need to cut a more narrow column to effectively do a PST, and that the Luther Pass snow at 7700' is pretty damn stable. ECTN26 on the density change between Saturday's new snow and Sunday's new snow - no full propagation across the column. The two crust layers with facets in between were buried about 110 cm deep and we could easily visually identify the facets (squarish and cup-like). The new snow at that elevation @Luther definitely bridged above this layer, and the facets did not seem to propagate a collapse very easily during PST ... numerical results are invalid since my column was wider than the saw blade length, but it took a lot of hacking well up the 100 cm long column before the upper crust collapsed onto the lower crust.

Great day for practicing skills ... I even learned some new tricks with multiple burial scenarios!

[nightpanda]

Any mags from the bay area heading to Kirkwood tomorrow (or any days this week) that can offer a ride? It is going to be $$$

[MrSmith]

But I think we're seeing a good number of slides starting at density transitions in the storm snow and stepping down to the facet layers. There are so many ways for the snowpack to fail right now... not good.

[Tyrone Shoelaces]

When things slow down, I'm hoping to go on a midnite bomb run with him.

That would make a cool write up.

[powdork]

I would be interested to see what Schralph and Harpo find at Luther. A bit of put digging may be in my future. PD, where did you skin and what did you observe today?

mini golf today. things SEEMED bomber. we did not dig a pit. our go decision was based on a visual inspection of the snowpack from a distance i guess. it looked good.

[splat]

That would make a cool write up.

Wishin' I hadn't sold my camera with the remote flash setup.