GNFAC Avalanche Forecast for Wed Feb 19, 2025
This is Mark Staples with the avalanche forecast for Wednesday, February 19th, at 7:00 a.m. sponsored by Klim and the Avalanche Alliance. This forecast does not apply to operating ski areas.
Yesterday some snow fell in most areas with the mountains near Big Sky and Bozeman getting 2-4 inches. Further south a trace to 2 inches fell. More importantly, the strongest winds blew yesterday morning to midday from the NW at 15 mph gusting to 40 mph.
This morning temperatures are hovering near 10 degrees F. Winds are blowing 8-18 mph from the W and NW gusting in the low 20s. Skies are mostly clear.
Today clouds will increase as moisture moves over the area. Temperatures should warm into the low 20s F. Winds will slowly shift direction and blow from the SW but not increase in speed. Tonight a few more inches of snow should fall.
WIND is really driving the avalanche danger now (especially with so much powder available to drift) and it looks like we’ll have a few days without much wind. Strong winds will blow in northern and central Montana tomorrow and Friday which could affect the Bridger Range. Otherwise, the next significant wind may not arrive until Sunday.
Storm totals since Valentine’s day are impressive (weather log):
- Bridger Range - 37” of snow (3.2” SWE)
- Big Sky - 46” of snow (2.3” SWE)
- Gallatin Range, S. Madison Range, Cooke City, Island Park and West Yellowstone - 17-27” (1.6-2.2” SWE)
All Regions
There is simply a lot of snow and riding conditions are as good as it gets; however, remember that most avalanches happen within 24-48 hours after snowfall or wind.
Wind slabs - In all areas, the primary avalanche problem is wind slabs as Dave found near Island Park and a skier found on Saddle Peak yesterday where a wind slab broke 18 inches deep, 50 feet wide and ran a significant distance. Winds yesterday from the NW did most of the drifting, and winds shifting to the SW today may find a little snow to move. Fortunately there are many slopes unaffected by winds.
Storm slabs - The new snow should be bonding to itself and stabilizing quickly, but there is just a lot of powder out there creating some uncertainty. Because there’s still a possibility of storm slabs, I’d select terrain with a clean runout today free of terrain traps, rocks, and trees if getting onto steeper slopes.
Persistent slab avalanches - A problem in the Lionhead area, southern Madison Range (Taylor Fork, Teepee, Carrot, etc.) and southern Gallatin Range. The problem layer is small facets that formed in late January, now buried 2-3 feet deep. The Cooke City area may still have this problem, but it is buried deeper and seems to be less of an issue. A snowmobiler was caught in a small persistent slab avalanche on Lionhead on Thursday BEFORE all this snow fell. The most likely places to trigger one of these slides is on a slope with extra loading from yesterday’s winds, but I think there will still be slides on this layer on non-wind loaded slopes that will surprise you..
Travel advice today - Stay off slopes or portions of slopes with fresh wind drifting. Consider the consequences of triggering a soft storm slab avalanches even though the likelihood of these slides is going down. If traveling in areas with a persistent slab avalanche problem, I’d simply avoid avalanche terrain for now and give the faceted layer time to stabilize.
The avalanche danger in all areas is CONSIDERABLE in places with fresh wind loading where you will trigger a slide.. The danger is MODERATE on all other slopes not loaded by recent winds
Special Note - Tree Wells
With the abundance of recent snow, tree well immersion is a serious concern. Don’t ride too close to the base of trees, and keep continuous communication with your partners and know where they are even when not in avalanche terrain.
Upcoming Avalanche Education and Events
Our education calendar is full of awareness lectures and field courses. Check it out: Events and Education Calendar
TOMORROW, February 20, 4-7 p.m. Beacon BBQ at Uphill Pursuits in Bozeman. Come try out different brands of avalanche transceivers (or practice with your own!) with coaching from Friends of GNFAC instructors and free hotdogs.
February 28 - March 2, Bozeman Splitfest 2025 - Celebrate all things Bozeman backcountry and raise funds for GNFAC. Enjoy demos, clinics, free food and beer from MAP. Connect with fellow outdoor enthusiasts and soak up the winter stoke.
Every weekend in Cooke City: Friday at The Antlers at 7 p.m., Free Avalanche Awareness and Current Conditions talk, and Saturday from 10 a.m.-2 p.m. at Round Lake Warming Hut, Free Rescue Practice.