Caution advised for snow falling off of building roofs. Park accordingly.

Dangerous avalanche conditions may already exist in many back country areas, please call the Recorded Avalanche Advisory 406-587-6981 for the most current conditions.

Today: Breezy. Mostly cloudy in the morning then becoming partly cloudy. South winds 15 to 20 mph. Highs 30°F to 36°F.

Tonight: Breezy. Mostly cloudy. Slight chance of snow in the evening...then chance of snow after midnight. Southwest winds 15 to 20 mph. Chance of snow 40 percent. Lows 15°F to 21°F.

Thursday: Snow likely in the morning...then snow in the afternoon. Snow accumulation of 2 to 4 inches. South winds around 15 mph early in the morning. Chance of snow 80 percent. Highs 22°F to 28°F.

Thursday Night: Colder...snow. Snow accumulation of 2 to 3 inches. Total snow accumulation 4 to 7 inches. Chance of snow 90 percent. Lows -1°F to 5°F.

Friday: Colder. Cloudy with a 50 percent chance of snow. Highs 6°F to 12°F.

Friday Night: Colder. Mostly cloudy with a 20 percent chance of snow. Lows -4°F to -10°F.

Saturday: Partly cloudy. Highs 1°F to 7°F. Wind chill readings -15°F to -25°F.

Saturday Night: Partly cloudy in the evening then becoming mostly cloudy. Lows -6°F to -12°F.

Sunday: Mostly cloudy in the morning then becoming partly cloudy. A 20 percent chance of snow. Highs 4°F to 10°F.

Sunday Night: Partly cloudy in the evening then becoming mostly cloudy. A 20 percent chance of snow. Lows -5°F to -11°F.

Monday: Mostly cloudy with a 20 percent chance of snow. Highs 7°F to 13°F.

Monday Night: Mostly cloudy with a 30 percent chance of snow. Lows -5°F to 1°F.

Tuesday: Mostly cloudy with a 30 percent chance of snow. Highs 11°F to 17°F.

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Mountain Weather

In the last 24 hours the southern mountains have picked up 2 to 4 inches of new snow while the northern mountains received only a trace to an inch. Mountain temperatures are in the mid-twenties Fahrenheit with south to southwest winds averaging 20 to 30 mph and gusts in the 40s. Today will be warm and windy under partly cloudy skies. Tonight clouds will increase and snow showers will drop 2 to 3 inches of snow down south and a trace to one inch in the northern mountains.

Snowpack and Avalanche Discussion:

The Bridger and Northern Gallatin Ranges:

The Bridger and northern Gallatin Ranges have the same weak layer as everywhere else, but they have better stability simply because they have not gotten as much snow. In the Bridger Range yesterday, Mark and his partner toured near Fairy Lake while Eric took a lap on Saddle Peak. They both found that days of strong winds made wildly variable surface conditions. The west side of the range is unscathed, but the east side has ribs of wind scoured sastrugi and wind deposits of dirt scraped from the ridgelines. Mark still found plenty of near surface facets too, but their distribution was random because of the winds. For today the Avalanche Danger is rated MODERATE on all wind-loaded terrain and LOW Avalanche Danger on all other slopes.

Southern Gallatin and Madison Ranges, the Lionhead area near West Yellowstone and Cooke City:

Since Monday about five inches of snow has fallen around Big Sky, seven inches near West Yellowstone and a foot outside Cooke City. During this time strong winds out of the southwest created deep drifts. In terms of stability, this snow is a game changer because it buried much weaker snow that was at the surface (video). Clear weather last week created small faceted crystals in the top few inches of the snowpack. Some areas (Beehive Basin, Town Hill outside Cooke City) also grew some surface hoar (photo). The type of crystal is not important, but the fact that we buried a layer of very weak snow is. Yesterday, shooting cracks were reported outside Cooke City and the Big Sky Ski Patrol got avalanches to break on wind-loaded slopes that propagated further than they had in the previous weeks. Both of these are signs of increasing instability and red flag warnings that backcountry travel is getting serious.

For today, any slope with a wind-load has a CONSIDERABLE Avalanche Danger since it's likely someone can trigger an avalanche. On slopes without a wind-load the Avalanche Danger is rated MODERATE.

* * Tighten It Up * *

Our days of very good snow stability are on their way out, quite possibly for a long time. Tomorrow's storm could spike the avalanche danger rapidly and by the weekend natural and human triggered slides could be common. We are bracing ourselves. People have been getting away with murder: multiple skiers and riders on a slope at the same time, not checking the snowpack of their line, uphill tracks crossing starting zones and folks parking in runout zones to name a few. The days of getting away with sloppy backcountry travel are coming to an end. During a Low danger it's easy to feel smart since there's no consequence for bad behavior. With more snow it's going to get serious out there. Take stock and tighten up your scene. The wiggle room for error is bound to get razor thin.

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, PHOTOS, SNOWPITS, and VIDEOS

1. For links to Articles, Education and (photos) and (videos) listed in the above report, please visit this Link.

2. They have recently uploaded more photos and snowpits to their web site, more than what are linked in the advisory above.

3. They have creating a series of "How To…" stability test videos. So far they have clips on performing a CT and ECT. They are located under Stability Tests on their Resources page.

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