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. Also, see the Avalanche Advisory posted below.

Today: Cloudy with scattered snow showers. Chance of snow 40 percent. Highs 28°F to 34°F.

Tonight: Breezy. Cloudy with a 40 percent chance of snow. Northeast winds 15 to 20 mph in the late evening and overnight. Lows 9°F to 15°F.

Saturday: Mostly cloudy with a 30 percent chance of snow. Northeast winds around 15 mph until late afternoon. Highs 23°F to 29°F.

Saturday Night: Mostly cloudy in the evening then becoming partly cloudy. A 30 percent chance of snow. North winds around 15 mph in the evening. Lows 5°F to 11°F.

Sunday: Mostly cloudy with a 30 percent chance of snow. Highs 14°F to 20°F.

Sunday Night: Colder. Partly cloudy. Lows -2°F to -8°F. Wind chill readings -20°F to -30°F.

Monday: Partly cloudy. Highs 16°F to 22°F. Lowest wind chill readings -10°F to -20°F in the morning.

Monday Night: Partly cloudy. Lows -2°F to 4°F.

Tuesday: Partly cloudy. Highs 20°F to 26°F.

Tuesday Night: Partly cloudy with a 20 percent chance of snow. Lows 6°F to 12°F.

Wednesday: Partly cloudy with a 30 percent chance of snow. Highs 22°F to 28°F.

Wednesday Night: Mostly cloudy in the evening then becoming partly cloudy. A 30 percent chance of snow. Lows 4°F to 10°F.

Thursday: Partly cloudy with a 30 percent chance of snow. Highs 18°F to 24°F.

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Mountain Weather

Under partly cloudy skies and very light winds, mountain temperatures are in the upper teens Fahrenheit this morning. For the next 24 hours winds will remain 5 to 15 mph out of the southwest with temperatures reaching the mid-20s Fahrenheit under increasing cloud cover. A few flurries may dust the southern ranges, but no accumulation is expected. Tomorrow the weather pattern will change in favor of snow, so do not despair.

Snowpack and Avalanche Discussion:

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

The snowpack throughout southwest Montana is adjusting to the weight of last week's big snowstorm. Although there are some local differences in snow depth and layering, we've identified some helpful generalizations and patterns. Avalanche activity, as well as our snowpits, highlights two concerns:

1. A weak layer under the new snow.

Small grains of facets and/or feathery surface hoar crystals are easily seen as a darker stripe under the new snow. This weak layer is a prominent concern in the mountains from Big Sky to West Yellowstone. Last Saturday, immediately after the storm, an Montana State University graduate student got unstable results in 23 out of 28 Extended Column Tests at Bacon Rind. Yesterday, his research yielded only 9 of the 28 tests breaking clean, a positive trend towards stability.

2. Thin snowpacks: areas where the snow was less than three feet deep before the storm.

Zones with a thinner snowpack are comprised of well-developed weaker facets, but luckily this problem is not on most slopes. Mark and others found this around Cooke City (photo, photo) and it's also seen in the Bridger Range (photo), on Mount Ellis and Mount Blackmore, and near Big Sky. Sinking deep into the snow after stepping out of your skis or off your snowmobile is evidence of a weaker and possibly unstable snowpack.

It is becoming more difficult to trigger an avalanche, but determining which slopes are dangerous requires diligence and work. Dig, test and heed signs like "whumphs" or shooting cracks which warn us the snow is unstable. Today, in the Bridger, Gallatin, and Madison Ranges including the Lionhead area, the Avalanche Danger is rated MODERATE.

Near Cooke City, Mark is mostly finding stable and strong snow up to ten feet deep (video). These mountains lack a weak layer under the new snow and the primary avalanche concern is on steep, thin snowpacks. For today, the Avalanche Danger is rated MODERATE on slopes steeper than 35 degrees and LOW Avalanche Danger elsewhere.

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), (snowpits), or (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.