CAIC

Details

Date: 2011/02/07

Observer: Brian Lazar
Organization: Forecast Staff, Colorado Avalanche Information Center

Location

BC Zone: Front Range
Area Description: Berthoud Pass, west side. North to Current Creek

Weather

Ridgeline Wind Speed: 20-30 mph
Ridgeline Wind Direction: W
Wind Loading: Moderate
Sky Cover: Overcast
Depth of New Snow: 6 cm
Depth of Total Snow: 220 cm
Most Significant Precip Rate: S2 - 2 cm/hr
Weather Description: snowing on and off most of the mornign and afternoon. Seasonal temps. Mod to strong winds from W and NW. Stronger on east side of pass.

Snowpack

Snowpack Description: Storm snow is inverted. Heavier snow on top of less dense snow. The upper 1 to 2" heavily wind effected and turning into thin wind crust. Storm slab is now about 2 feet thick, and not bonding well. Most problematic aspects are E through S as there is a crust/facet combo there....these areas are most reactive.

Snowpack Obsvervation #1

Cracking: Minor
Collapsing: Moderate
Persistent Weak Layer: Yes
Comments: widespread collapsing, most notable on SE aspects near treeline.

Avalanches

Date

Location/Path

Elev

Asp

Type

Trig

SizeR

SizeD

2011/02/07

Berthoud Pass

2011/02/07

Berthoud Pass

AS / r

Media

Images

$Figure 1: fracture line profile near remotely triggered slide in Teacup Bowl. Slide ran on facet layer on top of crust approximately 2 feet down. (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/4jlwkymot40mn9ksmg8zxsdu184e?ixlib=php-3.1.0&s=7065ffdea2dc6bf2fa75f961177eca01','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)$ $Figure 2: remotely triggered fracture in Teacup. This is part of the crown, abut 2 feet thick. (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/tssm3xtjanbyzqgnx71gjpo5sjf1?ixlib=php-3.1.0&s=4c8c825fece17d57bc3e42ebc46e51aa','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)$ $Figure 3: fracture went as appraching slope from 100 feet away. extended from where photo is taken to right hand side of photo (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/k2qythk6pu9t35vobbn4c1p0g0v7?ixlib=php-3.1.0&s=a006eb3b7d3d5f026ae5a74534db2b92','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)$ Figure 4: Looking at crown. Bed surface was crust. Weak layer was facet on top of crust. (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/l4q64yamhtgbk8e8knhb61fexutz?ixlib=php-3.1.0&s=fae27a4b60a0fb0afec24e95bf59ed19','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)

<b>Figure 4:</b> Looking at crown. Bed surface was crust. Weak layer was facet on top of crust. (<a href=javascript:void(0); onClick=win=window.open('https://caic-production.imgix.net/l4q64yamhtgbk8e8knhb61fexutz?ixlib=php-3.1.0&s=fae27a4b60a0fb0afec24e95bf59ed19','caic_media','resizable=1,height=820,width=840,scrollbars=yes');win.focus();return false;>see full sized image</a>)