GNFAC Avalanche Forecast for Thu Oct 10, 2019

Since summer ended in late September the mountains have received snow storms almost weekly, and with each storm we received a report or two of small avalanches or signs of instability (weather and avalanche log). Last week ice climbers on the Sphinx found a shallow, weak snowpack (photo). On Saturday climbers in the same area had drifts of new snow collapse and “whumph” underneath them, then made a quick decision to head home (report). Instabilities have been generally small, but the size of slides and chances of triggering an avalanche rise with each snowstorm. Even small slides are deadly if they push you into a terrain trap like trees, rocks, gullies, or over cliffs.

It is barely fall, but with layers of snow piling up in the mountains bigger avalanches are possible. Avalanches this time of year are not uncommon, and have injured and killed people in past seasons (accident reports). If you plan to travel in the backcountry, whether skiing, climbing or hunting prepare for avalanches like you would all winter.

• Carry a beacon, shovel and probe at a minimum. Helmets are a necessity as well.
• Travel one at a time in avalanche terrain.
• Avoid steep slopes with fresh drifts of snow, especially where even a small slide could push you into rocks or trees, or pile up deep in a confined gully.
• Cracking and collapsing of the snow are bulls-eye information that the snow is unstable, and clear signs to avoid steep slopes.
• As the snow piles up it is a good idea to dig to see the layers below the recent snow. Avoid steep slopes if you find weak, sugary snow underneath new or drifted snow.

We are preparing for winter, setting up weather stations and beginning to collect snowpack information. If you have avalanche, snowpack or weather observations to share. Please submit them via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).