GNFAC Avalanche Forecast for Sat Jan 30, 2021

Not the Current Forecast

Good Morning. This is Alex Marienthal with the Gallatin National Forest Avalanche Forecast on Saturday, January 30th at 7:15 a.m. Today's forecast is sponsored by Cooke City Super 8/Bearclaw Bob’s and Spark R&D. This forecast does not apply to operating ski areas.

Mountain Weather

Since yesterday morning the mountains from Big Sky to West Yellowstone got 6-9” of new snow, and elsewhere got 3-5” inches. During yesterday’s heavy snowfall in the southern ranges, wind was south-southwest at 15-20 mph with gusts of 30-50 mph. This morning wind is 5-15 mph out of the west-northwest and temperatures are teens to low 20s F. Today temperatures will reach mid-20s F with west-northwest wind at 10-25 mph. Snow will continue with another 1-3” before skies begin to clear this afternoon.

Snowpack and Avalanche Discussion

In the mountains south of Big Sky to West Yellowstone new snow has added significant weight to a snowpack that contains multiple buried weak layers, and dangerous avalanche conditions exist. Since Wednesday night these mountains got 18-26” of snow equal to 1.5-2.1” of snow water equivalent (SWE). Avalanches large enough to bury or injure a person are easy to trigger within the new snow, especially where yesterday’s moderate to strong southwest wind formed thicker slabs (Dave’s video from Lionhead). Larger avalanches can break deeper on buried weak layers and could be triggered from lower angle terrain below and adjacent to steep slopes. On Thursday, skiers in the southern Gallatin Range triggered a large collapse in low angle terrain (photo). Today the avalanche danger is rated CONSIDERABLE. Conservative decision making and cautious route finding are essential.

Near Big Sky and Bozeman, 3-6” of low-density new snow (0.3-0.4” SWE) and light to moderate west-northwest wind formed fresh slabs that can be triggered by skiers and riders. Yesterday afternoon a skier in the northern Madison Range triggered an avalanche in the new snow which propagated wide and broke deeper into weak sugary snow below (photo). Today similar human triggered avalanches are possible, especially on wind-loaded slopes. The avalanche danger is MODERATE due to fresh drifts adding weight to a weak snowpack.

Near Cooke City, since Thursday morning the mountains got 6-8” of new snow equal to 0.6” of snow water equivalent. Yesterday, moderate south-southwest wind formed fresh drifts that are possible to trigger. These slabs can break deeper and wider on a weak layer of surface hoar or facets buried 18-24” deep. Doug was in Cooke City on Monday and found this layer in his snowpits and in the crown of a snowmobile triggered avalanche (video, photo of avalanches). Be cautious of steep wind-loaded slopes and avoid steep slopes where you suspect buried weak layers exist. Large avalanches are possible to trigger and the avalanche danger is MODERATE.

If you get out, please send us your observations no matter how brief. You can submit them via our website, email (mtavalanche@gmail.com), phone (406-587-6984), or Instagram (#gnfacobs).

Avalanche Warning

King and Queen Fundraiser

February 6th and 7th, Saturday and Sunday, at Bridger Bowl. Due to the pandemic it is a GS race this year. Prizes will be awarded for the fastest race results AND separate prizes for folks who raise the most money over $500. No racing is necessary to compete for the fundraising prizes. Info is HERE.

Upcoming Avalanche Education and Events

See our education calendar for an up-to-date list of all local classes. Here are a few select upcoming events and opportunities to check out:

Every Saturday in Cooke City, FREE snowpack update and rescue practice at the Round Lake Warming Hut between 10 a.m. and 3 p.m. Poster with More Info.

February 5 and 6, Women's Companion Rescue Clinic with SheJumps. Registration HERE.

February 19 and 20, Companion Rescue Clinic. Registration HERE

February 26 and 27, Women's Companion Rescue Clinic with SheJumps. Registration HERE.

The Last Word

February 6th and 7th is the King and Queen Fund-raiser at Bridger Bowl. Due to the pandemic it is a GS race this year. Prizes will be awarded for the fastest race results AND separate prizes for folks who raise the most money over $500. No racing is necessary to compete for the fundraising prizes. Info is HERE.