New Observation Platform

CBACAnnouncements, Backcountry Notes

The CBAC is rolling out a new observation platform this season, in partnership with the National Avalanche Center.  This platform will be used by most avalanche centers around the country, so you’ll be looking at the same familiar tools if you go skiing or riding in California, Washington, Wyoming, Idaho, etc.  The platform also improves our analysis capabilities and data management, and is better suited for future developments like a mobile app.

The observation form is intuitive. You can choose between the short form for simple text descriptions and photo uploads, or a long form which allows you to enter avalanche and weather details, along with problem assessments.  The observation viewer has three tabs: observations, avalanches, and visualization tools.  Check them out!  There are a few examples below. As with any new tool, there will be a bit of a learning curve for all of us, but hopefully you’ll find some of the new features helpful for your backcountry adventures.

FAQ’s

Do I have to provide a location when I submit an observation?

Yes, the form requires a location name and a map pin.  The location is used in our analysis tools and it is helpful for us to understand how your observation fits into a bigger picture of regional patterns.  If you’d prefer to protect your secret stash, you can drop a pin at the trailhead where you started from or in the general area of travel.

What about observations from previous seasons?

All observations from previous seasons are archived on our website still. You can find them under “Resources” from the website menu.  We are working on ingesting historical avalanche data into this new tool.

Where is the old avalanche rose?

The new visualization tools allow you to filter your search spatially or by avalanche size, aspect, elevation, trigger, problem, etc, similar to the rose.  We are currently working on linking the new database to our avalanche rose so that it still functions.  We’ll add it back to the website when/if that happens.

What if I don’t want to fill out an observation form?

You can still text us (970-444-2170), email us (cbavalanche@gmail.com), or tell us what you saw at the trailhead.

A mobile app?

The Northwest Avalanche Center has been developing a mobile app with offline functionality.  We will be working with them to make this resource available to our community in the future.

 

 

CBAC 2022/23 Annual Report

CBACAnnouncements, Avi Blog, Backcountry Notes, News

CBAC’s 2021/22 Annual Report is available to view or download here.  The report relives one of the biggest winters of this century, along with the outreach and operational accomplishments of the CBAC.  We also recognize the many sponsors, donors, and partners who are critical to our mission.  Thank you!

More wet slab activity on Whetstone

CBACCBAC Observations

Date of Observation: 05/17/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: M Face on Whetstone. Viewed from Mt. CB

Observed avalanche activity: Yes
Avalanches: Another fresh wet slab on Whetstone. M Face ran sometime this afternoon.

Photos:

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Shallow freeze on Gothic

CBACCBAC Observations

Date of Observation: 05/17/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Gothic Peak, traveled on southerly and easterly aspects to 12,600′

Observed avalanche activity: Yes
Avalanches: The bulk of recent avalanches have been D1-1.5 wet loose on northerly aspects N/ATL, where the snow is still in a transitional phase.
Weather: Scarp Ridge (@12k) had a minimum temp of 37 last night under clear skies. Mountain temps rose to the mid 40’s to mid 50’s, with partly cloudy skies developing by mid day. Calm winds where we traveled.
Snowpack: About 5″ refreeze which was just enough for mostly supportive boot pen and supportive ski pen before sunrise. Good corn around 8:30 a.m. on easterly aspects. Once crusts broke down later in the morning, ski pen became trapdoor near rocky areas and trees. It was easy to trigger small wet loose avalanches, but they didn’t gain volume; just ran slowly down existing runnels. Cornices are still big and saggy looking; we chose routes that avoided being underneath them given the warm day.

Photos:

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April wet slab activity from West Brush and Copper Creek

CBACCBAC Observations

Date of Observation: 05/10/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Copper Creek and West Brush Creek areas, viewed from Whiterock

Observed avalanche activity: Yes
Avalanches: Numerous previously undocumented D2 to D3 wet slabs likely ran during our April 9 to April 13 wet cycle. I coded their failure dates during the peak of the cycle 4/10 – 4/11, although I suspect activity was distributed across a wider date range than that.

Photos:

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April wet slab activity from Copper Creek

CBACCBAC Observations

Date of Observation: 05/10/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Copper Creek area

Observed avalanche activity: Yes
Avalanches: Numerous previously undocumented D2 to D3 wet slabs likely ran during our April 9 to April 13 wet cycle. I coded their failure dates during the peak of the cycle 4/10 – 4/11, although I suspect activity was distributed across a wider date range than that.

Photos:

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Dust on crust and a recent wet slab

CBACCBAC Observations

Date of Observation: 05/12/2023
Name: Zach Guy

Zone: Northwest Mountains
Route Description: Mt. Axtell 4th Bowl

Observed avalanche activity: Yes
Avalanches: A recent-looking large wet slab in Evan’s Basin. I’m guessing it ran sometime in the past few days.
Weather: Partly cloudy skies. Light northeast winds.
Snowpack: Less than 1″ of new snow above 10k, with isolated drifts up to 5″ from northeasterly winds ATL. Marginal refreeze due to last night’s cloud cover and insulating new snow, but the snow surface remained supportive under skis with good corn-like skiing through 9:30 a.m on northeast aspects. No signs of instability this morning.

Photos:

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Pow, corn, and wet loose on White Rock

CBACCBAC Observations

Date of Observation: 05/09/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Red Ridge to Queen Basin to Whiterock Mtn

Observed avalanche activity: Yes
Avalanches: Skier triggered and observed a few fresh natural wet loose avalanches on high, north-facing terrain up to D1.5 in size.
Numerous previously undocumented wet slabs from the April cycle, D2-D3. I’ll document those in a separate ob later this week.
Weather: Clear to few clouds, warm temps, light breeze.
Snowpack: Wet loose avalanches became reactive to ski cuts by mid day on ATL northerly terrain, where the top 6″ of dry powder was just now transitioning to wet snow. Elsewhere, the snow surface has matured through numerous melt-freeze cycles and wet loose avalanches appeared to be unreactive, even on steep terrain late in the day. The snow surface remained supportive to skis through 4 p.m. at all elevations except for a few spots near evergreen trees below treeline.

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Wet collapses and a couple small skier triggered slides

CBACCBAC Observations

Date of Observation: 04/28/2023
Name: Zach Guy

Zone: Northwest Mountains
Route Description: Upper Slate and Yule Pass areas. Traveled mostly on easterly and northerly aspects to 12,600′

Observed avalanche activity: Yes
Avalanches: On north-facing terrain ATL, I skier triggered a thin wind slab (~6″ x 8′) and a loose dry avalanche that both ran about 800′ (D1s).
Wednesday’s sunny weather after the storm spurred a wet shed cycle around the compass except for high northerlies. These were mostly wet loose, D1-1.5, and a handful of slabs up to D2. Not sure if they were moistening storm slabs or wet slabs; the debris looked fairly wet.
Weather: Clear, unseasonably cool temps. Moderate northwest winds were blowing the 1″ of new snow around with small plumes off of high peaks.
Snowpack: 1″ of new overnight and winds formed isolated, thin wind slabs ATL. These appeared to be bonding well on solar aspects; got one to pop on a crossloaded north facing slope. There’s up to 10″ or so of recent storm snow from the Tuesday night storm which hasn’t fully transitioned yet and could continue to produce more wet loose activity this weekend, especially to human triggers. At 1 p.m. while skinning up Yule Creek (~10k’, fairly flat terrain), we were getting widespread collapses on the dust layer, which was about 6″ to 8″ deep and saturated. Most collapses were a ski length or two wide, but some produced shooting cracks up to 30′ or 40′. This suggests there is potential for thin wet slabs this weekend as well, similar in character to the avalanches on Schuylkill Ridge shown below.

Photos:

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Earth Day was too hot for the powder day

CBACCBAC Observations

Date of Observation: 04/22/2023
Name: Evan Ross

Zone: Northwest Mountains
Route Description: NE-E-SE 9,500-11,500. Purple Ridge Area.

Observed avalanche activity: Yes
Avalanches: At 1pm, wet loose avalanches were reactive on NE and E below 11,300ft. These were generally small, but where they could run and accumulate mass they became large in size. We skier triggered several small wet avalanches and one become large in size. Another party had triggered more wet avalanches in similar terrain.

Weather: Convective snow showers with some moderate winds and drifting snow during those periods. The greenhouse was in full effect.

Snowpack: Recent storm totals were around 20 to 25cm at 11,000ft. Less snow at lower elevations and more snow at higher elevations… On the lee side of Purple Ridge, the drifts were a couple of feet thick. It was difficult to assess how far the thicker drifts extended into the slopes below. Wind slabs felt stubborn, but there was a notable lower-density layer of snow near the bottom of the drifts.

Snow surfaces become moist to wet on the sunny aspects, and thick/moist on northerlies BTL.

Photos:

6250