GNFAC Avalanche Forecast for Mon Nov 4, 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 Monday, November 4th. Today’s update is sponsored by Stronghold Fabrication and Community Food Co-op.

*Note: Bridger Bowl Ski Area is closed and there is no avalanche control or ski patrol services. Backcountry conditions exist. Workers are setting up for the season and making snow. Please stay clear of work areas, snow guns, chair lifts and other equipment.

Mountain Weather

Over the weekend the mountains did not get any snow except for 1” in Hyalite on Saturday night. Temperatures were 20s to mid-30s F with westerly wind at 15-25 mph. Last night the mountains near Cooke City and Hyalite got 2-3” of snow with no snow elsewhere. This morning temperatures are 20s to low 30s F, and wind is westerly at 10-15 mph with gusts of 25-40 mph.

Today will be mostly cloudy with a chance for 1-3” of snow near Bozeman, Big Sky and Cooke City, and partly sunny with no snow near West Yellowstone. Through the week, temperatures will be mid-20s to mid-30s F under partly sunny to mostly cloudy skies with wind at 20-30 mph out of the west-northwest. The next chance for snow is next weekend.

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

On Saturday, skiers in Beehive Basin were able to easily trigger fresh drifts of snow (photos and details), and skiers in Hyalite reported a natural avalanche that broke below a large cornice (photo). Wind loaded slopes remain the primary place you can trigger an avalanche, and a few inches of new snow today will be drifted into fresh slabs that can easily be triggered. Be cautious of drifts on steep slopes, and avoid terrain where a small slide could push you into hazards like rocks, cliffs or trees.

Yesterday I went to Beehive Basin for an initial look at that area's snowpack structure and stability (video). The snowpack there is 1.5 to 2 feet deep and generally stable for now, which is similar to other places that we have visited or received observations from (Bridger video, Hyalite video). The snowpack lacks widespread buried weak layers and recent loading from snow and wind has been minimal. This makes overall stability good, but we have received reports of poor snowpack structure and unstable stability test results (snowpit, photo). These results indicate the need to carefully assess the snowpack on any steep slopes you plan to ski or ride.

This week, a lack of new snow will keep the snowpack mostly stable for now, but in the mountains temperatures will be cold enough to create weak, sugary snow (facets or depth hoar) in many locations. We will be on the lookout for these potential future weak layers as they form, so when more snow buries them we know where to expect avalanches. If you are out in the mountains, you can help us out by submitting an observation of the snow, weather or any avalanche activity you see.

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.

8 November, Ullr and Skadi Fest, 6-9pm @ Swiss Fit Montana and Ph.D. Skis

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.

23 November, Helena Snowdrifters, Avalanche Awareness and Partner Rescue Training, 9am-3pm at the Mako Building 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.