Today...Breezy. Cloudy with a 40 percent chance of snow. Highs 24°F to 30°F. Southwest winds 15 to 25 mph.

Tonight...Windy...snow. Snow accumulation of 4 to 6 inches. Lows 15°F to 21°F. Southwest winds 15 to 25 mph increasing to 20 to 30 mph after midnight. Chance of snow near 100 percent.

Saturday...Breezy. Snow likely. Snow accumulation of 3 to 4 inches. Total snow accumulation 7 to 10 inches. Highs 23°F to 29°F. Northwest winds 15 to 25 mph. Chance of snow 70 percent.

Saturday Night...Colder. Mostly cloudy. Chance of snow in the evening...then slight chance of snow after midnight. Lows 6°F to 12°F. Northwest winds around 15 mph in the evening. Chance of snow 30 percent.

Sunday...Mostly cloudy. Slight chance of snow in the morning...then chance of snow in the afternoon. Highs 21°F to 27°F. Southwest winds around 15 mph. Chance of snow 40 percent.

Sunday Night...Mostly cloudy with a 40 percent chance of snow. Lows 7°F to 13°F.

Monday...Mostly cloudy in the morning then becoming partly cloudy. A 20 percent chance of snow. Highs 22°F to 28°F.

Monday Night...Mostly cloudy. Slight chance of snow in the evening...then chance of snow after midnight. Lows 14°F to 20°F. Chance of snow 30 percent.

Tuesday...Mostly cloudy with a 30 percent chance of snow. Highs 28°F to 34°F.

Tuesday Night...Partly cloudy with a 20 percent chance of snow. Lows 9°F to 15°F.

Wednesday...Partly cloudy with a 20 percent chance of snow. Highs 29°F to 35°F.

Wednesday Night...Partly cloudy with a 20 percent chance of snow. Lows 7°F to 15°F.

Thursday...Partly cloudy with a 20 percent chance of snow. Highs 28°F to 34°F.

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Mountain Weather

Since yesterday morning the mountains near Cooke City and West Yellowstone received 3-6 inches of snow. The mountains near Big Sky and Hyalite Canyon received an inch and the Bridger Range remained dry. Strong winds continue. This morning they were blowing 20-40 mph from the West except near Cooke City where they were blowing from the North. Temperatures were in high single digits Fahrenheit near Cooke City and West Yellowstone and mid to high teens Fahrenheit everywhere else. Today, winds should decrease slightly and temperatures should warm into the 20s Fahrenheit. Snowfall will come again tonight. The southern areas will again do well with 3-6 inches. Closer to Bozeman and Big Sky, 1-3 inches should fall.

Snowpack and Avalanche Discussion:

The Bridger, Madison and Gallatin Ranges, the Lionhead area near West Yellowstone, the mountains around Cooke City and the Washburn Range:

Bull's eye information today involves recent avalanche activity, new snow, and strong winds. Many natural avalanches were observed. Yesterday the Bridger Bowl Ski Patrol found many naturals involving fresh wind slabs and easily triggered many sizeable avalanches with both explosives and ski cuts. One notable natural avalanche, on a Northeast aspect of Saddle Peak, broke 3-4 feet deep and 150-200 feet wide running to the top of the cliffs. This one seems to have broken on deeper layers of snow that had faceted and weakened in recent weeks. Another deep slab avalanche was observed on Fan Mountain on a South aspect. Further south, a skier triggered a wind slab in the Taylor Fork area, and a skier near Cooke City observed four recent avalanches involving fresh wind slabs. Plentiful new snow from early this week and continued strong winds will continue to form fresh wind slabs in most areas. A skier on Saddle Peak commented that it was "mostly just one big wind slab." These wind slabs are the primary concern today.

If recent avalanche activity, new snow and wind aren't enough of a problem, we've got one more. Isolated areas have a weak snowpack. These areas do not have a specific pattern with respect to aspect or elevation. The common factor is a relatively shallow snow depth which was less than 1 meter prior to this week's snowfall. Some slopes have been scoured during previous wind events while others at lower elevations simply have not received much snow. An avalanche on Saddle Peak, two on Lone Mountain at Big Sky, one on Fan Mountain, and several near Cooke City all highlight this instability that required the load of new snow and wind-blown snow to produce avalanches. At lower elevations, Doug found a slope in Beehive with this weak snow, and a skier on Mount Ellis found similar weak snow but felt okay skiing because it had not been stressed by enough new snow and wind-blown snow. Despite these findings, many slopes have a deep and strong snowpack where fresh wind slabs are the only concern.

For today, wind loaded slopes are widespread and have a CONSIDERABLE Avalanche Danger. All other slopes have a MODERATE Avalanche Danger.

Information provided by Doug Chabot, Mark Staples, and Eric Knoff from the Gallatin National Forest Avalanche Center.

If you have any snowpack or avalanche observations, drop them a line at mtavalanche@gmail.com or call: 406-587-6984.

For detailed Avalanche Terms utilized here, please see the Avalanche Glossary.