CAIC

CAIC: Colorado Avalanche Information Center

BC Zone Observation Report

Friday, December 9, 2016 at 12:00 AM
Vail & Summit County

Details

Date: 2016/12/09

Observer: Brent Herring
Organization: Public

Location

BC Zone: Vail & Summit County
Area Description: NTL-ATL, north aspect on the ridge

Weather

Weather Description: 20F, broken cloud cover, winds ENE 20mph, blowing snow

Snowpack

Snowpack Description: total depth 75cm fist hard storm slab 20cm finger hard wind slab 30cm faceting 25cm, gradient from four finger to fist ECTP6, Q2 on the new-old interface continuation ECTN13 on the depth hoar

Avalanches

Avalanche Description: NTL-ATL 12k, north aspect, 30-35 deg start zone, gradual convex rollover, R2D1.5, ~300' wide, triggered as I was approaching the start zone. Didn't explore the runout. A lot of hangfire that would funnel. Seemed low energy consistent with ECT results.

Date

Location/Path

#

Elev

Asp

Type

Trig

SizeR

SizeD

View

2016/12/09 ^†

1

TL

N

U

AS / r

R1

D1.5

Media

Images

<b>Figure 1:</b> straight down from the rollover (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/cpg6ucqz5gv3vw90xe4h1g3ydio0?ixlib=php-3.1.0&s=e95a0cb452530deca1940196e7d23937','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)

<b>Figure 2:</b> right start zone (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/il9qhaef2nlxdh1qc3x2g6bq5uqp?ixlib=php-3.1.0&s=3b50580265b534f0bac1eaba44a71733','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)

<b>Figure 3:</b> left start zone (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/2vtptaife8widd3jhur77eve87zo?ixlib=php-3.1.0&s=daa6b8a4c0de9480bb3d4752f191a393','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)

<b>Figure 4:</b> basal faceting (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/rehpjojo8oujxmt5xqdh4tl0qykg?ixlib=php-3.1.0&s=5cf5f2586cbb625c05d742c0f35da1cd','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)

<b>Figure 5:</b> Unusual loading NTL with the ENE wind. (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/0sqc911kos2ooh89eosixgkn1eg9?ixlib=php-3.1.0&s=d2e2567a84eec98280346d91fd0d6ce6','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)