GNFAC Avalanche Forecast for Fri Oct 25, 2019

Not the Current Forecast

This is Alex Marienthal with pre-season avalanche, weather and event information for the Gallatin National Forest Avalanche Center on Friday, October 25th. This information is sponsored by Mystery Ranch and World Boards, both supporters of Tonight’s Powder Blast fundraiser.

Mountain Weather

Since Monday the mountains received 7-11” of snow with some rain mixed in Tuesday evening. This morning temperatures are high 20s to mid-30s F and wind is 15-25 mph out of the west. Today, temperatures will reach mid-40s F and northwest wind will increase to 25-35 mph with gusts of 40-50 mph. Temperatures will cool to the 20s F Saturday morning, then drop to single digits to teens F on Sunday. Wind this weekend will be 15-25 mph and shift from northwest on Saturday to northeast on Sunday. Snow is likely Saturday morning with 6-12” possible throughout the advisory area by Sunday morning, except near West Yellowstone where 2-4” is expected.

We will update our Weather Log and Regional Conditions every morning with snowfall totals, and our Avalanche Activity list if we get a report.

Snowpack and Avalanche Discussion

All Regions

Winter arrived about a month ago, and has shown little sign of letting autumn get a word in. Settled snow depth in the mountains is 1-3 feet which provides sufficient coverage for early season skiing. However, this snow creates heightened early season avalanche hazard. This weekend, whether you ski, climb or hunt, it is essential to carefully choose terrain and diligently assess the snowpack.

Yesterday I went to Bridger to be reminded which parts of my gear broke before it was neglected for summer. I also got a look at the snow which was impressively deep and supportive for this time of year (photo). The snowpack story might change as cold temperatures turn snow into unsupportive, weak sugary facets, but for now the main avalanche hazard is from new snow and wind. Instabilities created by new snow and wind are most widespread during and immediately following storms, so this weekend avalanches are to be expected with the forecasted new snow and moderate wind.

Avoid steep slopes with fresh drifts of snow. Stay alert for signs of instability such as recent avalanche activity or cracking/collapsing of the snowpack. Either of these are a clear warning to avoid steep slopes. If you plan to ride any steep slopes, dig to the ground (it won’t take long) and check for weak layers that might break under the new snow.

Hunters, or anyone traveling alone or without avalanche rescue gear, should avoid avalanche terrain entirely (>30 degree snow covered slopes). Last week ice climbers in Hyalite triggered a small slide as they approached a climb (photo). Even small steep slopes can be deadly if an avalanche piles snow deep in a gully or pushes you into rocks or over cliffs. Regardless of your activity or terrain selection, it is best practice is to bring a partner, travel one at a time, and carry standard avalanche rescue gear (beacon, shovel, and probe on each person).

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).


Upcoming Avalanche Education and Events

Our education calendar is full of awareness lectures and field courses. Check it out and plan to attend one or two: Events and Education Calendar.

BOZEMAN

6 November, 1-hr Avalanche Awareness, 6-7pm @ REI Bozeman.

7 November, 1-hr Avalanche Awareness, 6-7pm @ Langford Hall, MSU.

12 November, 1-hr Avalanche Awareness, 6-7pm @ Montana Ski Tuning and Boot Fitters.

14 November, 1-hr Avalanche Awareness, 6-7pm @ South Hedges Hall, MSU.

14 November, 1-hr Avalanche Awareness, 6-7pm @ Uphill Pursuits.

20 November, 1-hr Avalanche Awareness, 6-7pm @ The Mountain Project.

4 & 5 December, Introduction to Avalanche w/ Field Course, Evenings of December 4 & 5 plus one field day either December 7, 8 or 14. Snowmobile specific field day offered December 14. More info and Register Here.

HELENA

6 November, 1-hr Avalanche Awareness, 6-7pm @ The Base Camp in Helena.

BILLINGS

19 November, 1-hr Avalanche Awareness, 6-7pm @ The Base Camp in Billings.

The Last Word

Our education calendar is full of awareness lectures and field courses. Check it out and plan to attend one or two: Events and Education Calendar.