18-19 | Gallatin National Forest Avalanche Center

A snowmobiler triggered this small wind slab near Lulu pass outside of Cooke City. Wind loaded slopes are main avalanche concern across the advisory area.

Number of slides

Number caught

Number buried

Avalanche Type

Soft slab avalanche

Trigger

Snowmobile

Trigger Modifier

u-An unintentional release

R size

D size

Bed Surface

O - Old snow

Problem Type

Wind Slab

Read more about Snowmobile triggered slide, Lulu Pass Cooke City

Images

Snowmobile triggered slide, Lulu Pass Cooke City

Slab Thickness units

centimeters

Single / Multiple / Red Flag

Multiple Avalanches

Advisory Year

18-19

Read more about Snowmobile triggered slide, Lulu Pass Cooke City

A snowmobiler triggered this small wind slab near Lulu pass outside of Cooke City. Wind loaded slopes are primary avalanche concern across the advisory area. Photo: J. Temple

Avalanche Details: Snowmobile triggered slide, Lulu Pass Cooke City
Forecast link: GNFAC Avalanche Forecast for Sat Nov 17, 2018

Cooke City, 2018-11-14

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GNFAC Avalanche Forecast for Wed Nov 14, 2018

Snowpack and Avalanche Discussion

Wind slabs are the primary avalanche concern across the advisory area. Avalanche activity earlier in the week and last weekend is bull’s eye information fresh winds slabs are easy to trigger (<a href="https://www.mtavalanche.com/images/18/ice-climber-triggered-slab">photo…;, <a href="https://www.mtavalanche.com/images/18/small-wind-slab-triggered-flander…; <a href="https://www.mtavalanche.com/images/18/middle-basin-avalanche">photo</a>…;, <a href="https://www.mtavalanche.com/images/18/skier-triggered-wind-slab-bridger…;).

Yesterday, calm winds and warmer temperatures gave recent instabilities a chance to stabilize. However, winds are forecasted to increase today which will form a fresh batch of wind slabs in upper elevation terrain. Watch for this problem around rideglines, gullies and cliff bands. Avoiding wind loaded slopes, primarily in steep-high consequence terrain will be the best way to avoid an avalanche incident. It’s important to remember that avalanches can be triggered while hiking up hill. Read a recent <a href="https://utahavalanchecenter.org/blog/34045">article</a> by the Utah Avalanche Center highlighting this problem.

An additional problem will be wet loose avalanches. This problem will stay confined to steep slopes facing the south half of the compass. Signs of instability such as roller balls and small point releases are obvious clues instability is on the rise. Move to colder/shadier aspects if these signs are present.

New this season, we added hyperlinks to the <a href="https://www.mtavalanche.com/weather/wx-avalanche-log">Weather and Avalanche Log</a> and a new Menu item <<a href="https://www.mtavalanche.com/avalanche-activity">Avalanches and SnowPits</a>> with information on avalanche activity and incidents.

It is early season and we are still formulating an overall picture of the snowpack. Our <a href="https://www.mtavalanche.com/photos">photos</a> page and <a href="https://www.mtavalanche.com/snowpits">snowpit profiles</a> detail our field days and are worth a look. If you get outside send us an observation via our website, email (<a href="mailto:mtavalanche@gmail.com">mtavalanche@gmail.com</a>), phone (406-587-6984), or Instagram (#gnfacobs).