Today...Breezy. Partly cloudy. Highs 24°F to 30°F. Southwest winds 15 to 25 mph.

Tonight...Windy. Partly cloudy. Lows 9°F to 15°F. Southwest winds 20 to 30 mph. Gusts up to 45 mph in the late evening and overnight.

Sunday...Windy. Partly cloudy with slight chance of snow in the morning...then mostly cloudy with chance of snow in the afternoon. Highs 21°F to 27°F. Southwest winds 20 to 30 mph. Chance of snow 50 percent.

Sunday Night...Breezy...colder. Snow likely in the evening...then snow after midnight. Snow accumulation of 2 to 3 inches. Lows -2°F to 4°F. West winds 15 to 20 mph. Chance of snow 80 percent.

Monday / Martin Luther King Jr Day...Colder. Snow in the morning...then snow likely in the afternoon. Snow accumulation of 2 to 3 inches. Total snow accumulation 4 to 6 inches. Highs 6°F to 12°F. West winds around 15 mph in the afternoon. Chance of snow 80 percent.

Monday Night / Martin Luther King Jr Day...Cloudy with a 20 percent chance of snow. Lows -1°F to -7°F. Wind chill readings -21°F to -31°F.

Tuesday...Breezy. Mostly cloudy with a 50 percent chance of snow. Highs 11°F to 17°F. Wind chill readings -22°F to -32°F.

Tuesday Night...Breezy. Cloudy with a 50 percent chance of snow. Lows -1°F to 5°F.

Wednesday...Breezy. Snow likely. Highs 18°F to 24°F. Chance of snow 70 percent.

Wednesday Night...Breezy. Snow likely. Lows 11°F to 17°F. Chance of snow 70 percent.

Thursday...Breezy. Not as cold. Snow likely. Highs 26°F to 32°F. Chance of snow 70 percent.

Thursday Night...Breezy. Snow likely. Lows 15°F to 21°F. Chance of snow 60 percent.

Friday...Breezy. Cloudy with a 50 percent chance of snow. Highs 26°F to 32°F.

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Mountain Weather

This morning in the northern areas near Bozeman and Big Sky, mountain temperatures were in the low 20s Fahrenheit and winds were blowing 20-40 mph from the West. Further south near West Yellowstone and Cooke City, temperatures were in the low teens Fahrenheit and winds were blowing 10-20 mph from the Southwest. Today will warm into the high 20s Fahrenheit and winds will increase ahead of an approaching cold front. Next week may get snow every day. While no snow will fall by tomorrow morning, we will see Tom Brady and the Patriots crush the Broncos this evening.

Snowpack and Avalanche Discussion:

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

During the last two weeks, avalanche conditions have become more variable, and some slopes are more prone to producing avalanches than others. Slopes that are more likely to produce an avalanche have:

• Wind deposited snow from Tuesday night's storm or other wind slabs. These wind slabs, whether new or old, can help propagate a fracture in the weak snow underneath them. Karl describes this situation in a video from the Bridger Range. Eric found a similar situation along Buck Ridge just south of Big Sky yesterday, and snowmobile guides also found it near Cabin Creek.

• Steeper slope angles near 38 degrees. With each increasing degree of steepness, the odds of triggering an avalanche increase. The difference between a 33 degree slope and a 37 degree slope is huge even though both are avalanche terrain.

• High elevation, rocky slopes usually above treeline. These areas usually have variable snow depths, wind slabs, and lots of potential trigger points.

Although conditions are variable, the snowpack throughout the advisory area is about 3 to 5 feet deep. In all cases where a slab is present, stability tests are producing clean fractures about 15-30 inches deep (in the middle of the snowpack). These tests are breaking on either surface hoar, a thin layer of near-surface facets near an ice crust, or on top of a thick layer of depth hoar.

Hyalite Canyon deserves special mention because it has more stable conditions than other areas. Recent wind slabs could produce an avalanche, and some slopes have a layer of near-surface facets that could also produce an avalanche. However, very few avalanches have occurred in this area, and skiers have been able to find many stable slopes. These facts, though, are not a free pass to ski any slope without careful evaluation.

Because the snowpack is not stressed by recent snow, the odds of triggering an avalanche have decreased. Unfortunately the layering of the snowpack has all the ingredients for an avalanche and human triggered avalanches are definitely possible. Today the Avalanche Danger is rated MODERATE.

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!

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.

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.