Monday: Mostly cloudy, with a high near 29°F. Southwest wind between 7 and 11 mph.

Monday Night: Cloudy, with a low around 18°F. South southwest wind between 11 and 13 mph.

Tuesday: A 20 percent chance of snow. Mostly cloudy, with a high near 32°F. Southwest wind between 14 and 17 mph, with gusts as high as 24 mph.

Wednesday: Snow likely, mainly after 11:00 am. Cloudy, with a high near 36°F. Breezy, with a southwest wind between 15 and 22 mph, with gusts as high as 30 mph. Chance of precipitation is 60%.

Thursday: A chance of rain and snow. Mostly cloudy, with a high near 39°F. Chance of precipitation is 40%.

Friday: A 20 percent chance of snow. Partly sunny, with a high near 34°F.

Saturday: A slight chance of snow. Partly sunny, with a high near 32°F.

Sunday / New Year's Day: Mostly sunny, with a high near 32°F.

 Hazardous Weather  Gibbon Falls Forecast  Mammoth Forecast  Midway Forecast  Norris Forecast  Old Faithful Forecast 

Mountain Weather

A dry-upper level weather disturbance is moving across southwest Montana producing strong gusty winds. This morning winds are blowing 20-40 mph out of the West-northwest with gusts reaching into the 50s. Mountain temperatures are in the mid teens to low twenties Fahrenheit with Cooke City being the coldest at 9°F. Today, temperatures will warm into the upper twenties Fahrenheit and winds will stay elevated through the morning hours with gusts in the 50s possible. Winds will gradually decrease this afternoon. A cool and dry pattern will persist over southwest Montana through Tuesday.

Snowpack and Avalanche Discussion:

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

Weather patterns this winter have been sporadic, making for variable snow conditions in our forecast area. Storms have been selective in their distribution of both snow and wind - developing unique snowpacks in individual ranges and even areas of the same range. Some areas have a deeper-stronger snowpack, mainly the northern Gallatin Range and mountains around Cooke City, while other locations consist of, as one friend puts it, "facet castles masquerading as a snowpack."

Yesterday, my partner and I took a pleasant walk up Mount Ellis. The snowpack from the meadow to the summit was comprised almost entirely of facets, making it possible to dig directly to the ground with my hand. On Friday, skiers in Beehive Basin found a different and more unstable snowpack. A two foot slab resting over facets near the ground provided an unstable structure capable of producing an avalanche.

Despite warm-calm weather at lower elevations yesterday, taller peaks in the northern Gallatin and Madison Ranges had large plumes of snow billowing off their summits most of the afternoon - visual evidence that active wind loading was taking place.

Today's primary avalanche concern is wind loaded slopes. Strong winds out of the west make upper elevation slopes with an easterly component the most prone to unstable snow.

Today - Human triggered avalanches are likely on wind loaded slopes steeper than 35 degrees where the Avalanche Danger is rated CONSIDERABLE. All other slopes have a MODERATE Avalanche Danger.

The Bridger Range:

The Bridger Range just doesn't have enough snow to harbor widespread instability. Most slopes have a thin-shallow snowpack lacking a slab. Mark and I found this type of snowpack on the Apron this past Saturday. However, upper elevation slopes, specifically those below ridgelines, do hold isolated pockets of wind drifted snow capable of producing an avalanche. The tricky part about this scenario is wind loaded slopes will provide the deepest snow cover and better riding conditions. If you are skiing or riding in the Brdiger Range, be cautious in wind loaded terrain and always be thinking about the consequences of an avalanche.

Today – Human triggered avalanches are possible on wind loaded slopes which have a MODERATE Avalanche Danger. Non-wind loaded slopes have a LOW Avalanche Danger.

The next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations, drop us a line at mtavalanche@gmail.com or call us at: 406-587-6984.

Beacon Parks

The Friends of the Avalanche Center installed a Beacon Training Park outside West Yellowstone last Friday. It's located south of town on the main snowmobile trail. Stop by and do a quick practice before heading off into the mountains!

EDUCATION, EVENTS, PHOTOS, SNOWPITS, and VIDEOS

1. We've recently uploaded more photos and snowpits to our web site, more than what are linked in the advisory.

2. We're creating a series of "How To…" stability test videos. So far we've got clips on performing a CT and ECT. There are located under Stability Tests on the Resources page.

3. Check out all our education programs, Click Here.

Information provided by Doug Chabot, Mark Staples, and Eric Knoff from the Gallatin National Forest Avalanche Center. For Events and Education, or Photos and Videos, please visit the Avalanche Centers Website!

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.