Colorado 2018-19 Colorado Weather and Stoke

[tball]

Do you have the snowpack graph with multiple years? (I'm never sure how to get that... Snotel site?)

Here are the keys, drive safely:
https://www.cbrfc.noaa.gov/station/sweplot/sweplot2.cgi?yrList=median&yrList=avg&yrList=2019&yrList=2018&yrList=2017&yrList=2016&yrList=2015&yrList=2014&yrList=2013&yrList=2012&yrList=2011&stationList=GZPC2&tavg=s&hsim=&index=&dbsvr=&indextitle=Blue+River%3fmedian.avg.2015.2014

You have to go back to 2011 to beat this season:

 

[tball]

Is Pali closed? How about that Beavers area?

Get on an airplane if your back is feeling better! I'm shooting for A-basin Tuesday and the following Sunday if @James or anyone else wants to make some turns.

I'm also hoping for some good skiing on Memorial Day weekend. Seems like high country biking is probably going to be a while. How long is it going to take to get the bike path open through Ten Mile Canyon? What a mess to clean up.

 

[nay]

You have to go back to 2011 to beat this season

I suspect if we looked at Snotel sites for all of the West that this season might beat 2011, even though it wasn’t close here. Pretty remarkable to see north, south, and central all get hammered.

I think 2015 is the most interesting season in the last decade for people who like to ski a long season here. There is a near steady Continental Divide snowpack from Feb - May and the season goes longer than some ‘bigger’ years because it just kept a snowing in small increments all the way through May. There was a peak of 10” more snow/water equivalent in 2014 than 2015, but 2015 didn’t lose any SWE during May while 2014 lost 13” (of water, not snow).



Continental climates tend to get very warm at the end of May and can lose 4” of snowpack per day. So while A-Basin is qualitatively excellent right now, just a couple weeks of straight warm weather can make the season end fairly average.

We need a huge April and May to get to July here, and we have only had sustaining snowfall so far. A week of warm weather will close Zuma, Pali, Beavers, and East Wall. Consistent cool weather with small reinforcing accums can keep it open like 2015.

It is still early.

 

[tball]

A week of warm weather will close Zuma, Pali, Beavers, and East Wall

Yeah, is next week warm enough to close the steep terrain due to wet slab risk? Or, will the goods survive to what looks like low pressure and cooler temps the following week?

Forecast temps in the 7-day forecast are a few degrees above average, but with somewhat mixed weather with clouds. We'll have to start looking at the stream flows for signs of the wet slab risk next week.

 

[nay]

Yeah, is next week warm enough to close the steep terrain due to wet slab risk? Or, will the goods survive to what looks like low pressure and cooler temps the following week?

Forecast temps in the 7-day forecast are a few degrees above average, but with somewhat mixed weather with clouds. We'll have to start looking at the stream flows for signs of the wet slab risk next week.

I don’t think it will be warm enough long enough for season ending web slab closures, but I bet East Wall will close some days as the rollers come down.

Of course, the mid-May sun is really strong so we’ll see. I think Al is going to want to keep East Wall viable through Memorial Day when Breck closes, but it may depend on how strong the next system is to refreeze the base.

 

[Mike King]

@James, you have an epic pass, don’t you?

 

[Ken_R]

Im game to ski a few more days in A Basin. I am also interested in skiing the Breck Alpine.

I am eyeing some big lines in the Backcountry but weather and conditions have to be just right.

 

[jmeb]

Loveland was creamy goodness today.

 

[SBrown]

...Seems like high country biking is probably going to be a while. How long is it going to take to get the bike path open through Ten Mile Canyon? What a mess to clean up.

I've heard mid-July. (or, it could be mid-July.)

 

[James]

@James, you have an epic pass, don’t you?

Sort of. I think Abay is $10.

 

[tball]

I've heard mid-July. (or, it could be mid-July.)

Oh boy, the Triple Bypass is July 13th and the Courage Classic is July 21st. Here's hoping they get the bike path open for those two huge events.

23 slides crossed the path! Great video in this story from 9news yesterday:
https://www.9news.com/article/life/...losed/73-b0daa883-2e6f-480f-b244-cc0e725e9c70

And, an article a few weeks ago in the Summit Daily:
https://www.summitdaily.com/news/lo...r-extended-recpath-closure-in-tenmile-canyon/

 

[Mike King]

Sort of. I think Abay is $10.

Have you skied Breck’s high alpine? It’s on your pass, for free, rather than having to stand in line to pay the VR employee tax of $10.

 

[tball]

Sort of. I think Abay is $10.

Limited time only deal for you at A-basin! Going fast and soon to be gone... forever.

I think Al is going to want to keep East Wall viable through Memorial Day when Breck closes, but it may depend on how strong the next system is to refreeze the base.

It's going to be interesting to see if Breck takes the wet slab danger as seriously as A-basin. We'll find out soon enough.

 

[nay]

Limited time only deal for you at A-basin! Going fast and soon to be gone... forever.


It's going to be interesting to see if Breck takes the wet slab danger as seriously as A-basin. We'll find out soon enough.

I think A-Basin has somewhat higher danger based on their terrain and aspects, especially with East Wall traverse under a pretty big number of slide paths, even though those seems to sluff more than anything.

Loveland had huge rollers coming off the Super Bowl ridge cornice on closing day that were almost reaching the groomer above Ptarmigan Roost. And that terrain slides all the time.

My thought was that A-Basin would have closed everything, and people were dropping some of those big cornices.

It’s tough to assess differences in risk management between ski areas given the variables, including risk tolerance. We know the ski area operators don’t have any liability for slides - A-Basin is very public about spring terrain closure considerations, and I think that makes them more conservative by default.

And also that they are part of a long term continental snowpack avalanche study and have water sensors on Pali.

 

[Mike King]

A-Basin is very public about spring terrain closure considerations, and I think that makes them more conservative by default.
.

I suspect it has more to a death in Alley 1 due to a spring wet slab avalanche.

 

[tball]

^^^ Yeah, the First Alley is now called David's Run, named for David Conway, 53, of Boulder who died in the avalanche there in 2005.
https://avalanche.state.co.us/acc/acc_co.php?accident=20050520

The fact Al skied through there just before the slide and reported the conditions he did has always stuck in my mind, and I'm sure his and changed the risk tolerance of the area following:

Less than 30 minutes before the avalanche occurred, area mountain operations director, Alan Henceroth, skied First Alley area where the slide occurred but did not see any signs of avalanche danger.

“Henceroth reported that his skis penetrated about one inch into the surface of the crust and that tracks from the day before were frozen in place and quite hard and rough,” said Abromeit.
https://www.summitdaily.com/news/a-basin-exonerated-in-avalanche-death/
​

I have good memories of skiing Pali down the bitter end with totally rotten snow and a 30ish inch base previously.

 

[Ken_R]

A Basin was good today. Wide range of snow surface conditions depending on TOD and Aspect. Totally normal in the spring but coverage is certainly above average.

Nice seeing a few Pugskiers!





Quite a few people hitting some BIG lines in the Backcountry nearby!

 

[Mike King]

Be careful in the backcountry— 7 (seven!) people were caught in avalanches in RMNP yesterday.

www.denverpost.com/2019/05/12/avalanches-rocky-mountain-national-park-saturday/amp/

 

[Ken_R]

Be careful in the backcountry— 7 (seven!) people were caught in avalanches in RMNP yesterday.

www.denverpost.com/2019/05/12/avalanches-rocky-mountain-national-park-saturday/amp/

It is generally very safe out there now but there is still a LOT of snow out there and all the danger that brings. At the very top off of the highest ridges and the top of couloirs in north or shaded aspects you can still find some wind slabs since the snow is still in winter condition. Cornice fall is a constant danger during the day. Wet slabs are also increasing with the warmer temps. Its all about timing and awareness.

I dont have much info on the RMNP incidents but looks to me that a bunch of people were going up/down the SAME slope in between rock features. It seems someone set off a windslab at or near the top and took a few people down. Sunday/Sat funday

 

[nay]

I suspect it has more to a death in Alley 1 due to a spring wet slab avalanche.

I have assumed that the fatality is what prompted the long term wet slab study at A-Basin, but this paper was presented in 2010 with a problem statement that the paper says was mentioned 6 years prior.

This is a good read for anybody who hasn’t seen it before, with some particular emphasis in backcountry comparison noting that early season avalanche control measures persist in effectiveness into the melt season.

http://arc.lib.montana.edu/snow-science/objects/ISSW_O-031.pdf

In conclusion, the problem statement mentioned 6 years ago reads: Although rare, crack propagation or wet slab avalanches which involve the entire snowpack are most likely to occur at the onset of sustained snowmelt. Based on findings presented here, we fail to reject this statement..

The problem statement is particularly concerning for backcountry skiers. As @Ken_R noted, there is a lot of snow with what appears to be winter conditions, but the first major diurnal water infiltrations of the melt season correlate to the greatest risk of web slab release.

This is exactly what is going to happen this week with temps generally not dropping below freezing at night, warm daytime temps, and full mid-May sun.