Today...Breezy...cloudy. Chance of snow in the morning...then rain likely and chance of snow in the afternoon. Snow accumulation up to 1 inch. Highs 37°F to 43°F. Southwest winds 15 to 25 mph. Chance of precipitation 60 percent.

Tonight...Breezy...snow. Snow accumulation of 3 to 6 inches. Lows 22°F to 28°F. Southwest winds 15 to 25 mph. Chance of snow near 100 percent.

Wednesday...Breezy. Snow in the morning...then snow and rain in the afternoon. Snow accumulation of 2 to 5 inches. Highs 34°F to 40°F. Southwest winds 15 to 25 mph. Chance of precipitation 90 percent.

Wednesday Night...Colder. Snow likely in the evening...then chance of snow after midnight. Snow accumulation of 1 to 2 inches. Total snow accumulation 6 to 14 inches. Lows 15°F to 21°F. Southwest winds around 15 mph. Chance of snow 60 percent.

Thursday...Cloudy with a 50 percent chance of snow. Highs 28°F to 34°F. Southwest winds around 15 mph.

Thursday Night...Mostly cloudy in the evening then becoming partly cloudy. A 30 percent chance of snow. Lows 11°F to 17°F.

Friday...Breezy. Partly cloudy with a 20 percent chance of snow showers. Highs 27°F to 35°F.

Friday Night...Partly cloudy with a 20 percent chance of snow showers. Lows 14°F to 20°F.

Saturday...Mostly cloudy. Chance of snow showers in the morning... Then chance of snow showers and rain showers in the afternoon. Highs 34°F to 40°F. Chance of precipitation 30 percent.

Saturday Night...Mostly cloudy with a 40 percent chance of snow showers. Lows 11°F to 17°F.

Sunday...Mostly cloudy with a 30 percent chance of snow showers. Highs 24°F to 32°F.

Sunday Night...Mostly cloudy in the evening then becoming partly cloudy. A 20 percent chance of snow showers. Lows 9°F to 15°F.

Monday...Mostly cloudy with a 20 percent chance of snow showers. Highs 26°F to 32°F.

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Mountain Weather

Yesterday morning, three to four inches of snow fell in the mountains from Big Sky to the Bridger Range. In the southern half of our region, six to seven inches accumulated. With temperatures in the upper teens Fahrenheit, winds are blowing from the west to southwest at 20-30 mph with gusts near 40 mph. Today will be partly cloudy with mountain temperatures reaching the high 20s Fahrenheit as wind speeds increase out of the southwest. More snow tonight will measure three to five inches in the north and five to eight inches down south by sunrise.

Snowpack and Avalanche Discussion:

The Bridger, the northern Madison and northern Gallatin Ranges:

In the northern mountains, yesterday's three to four inches of new snow was gooey and measured 10 to 12 percent density. Even with winds blowing, the slabs that formed were reported to be thin and not very touchy. Winds blew last night and will continue today. Recently formed wind slabs at the ridgelines are our biggest avalanche concern and avoiding wind pillows is the easiest way to mitigate the danger. Without notable weak layers in the snowpack, I expect avalanche activity to be limited to the new snow.

For today, the Avalanche Danger is rated MODERATE on all wind-loaded terrain and LOW Avalanche Danger everywhere else.

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

The southern mountains have received seven inches of dense snow with steady westerly winds. Wind-loaded slopes are the primary avalanche concern and I expect some natural avalanche activity at the ridgetops today. Besides windblown snow the snowpack in the south has a layer of facets a foot under the surface that may break from the new snow load. A quick hand pit should reveal its existence. This layer is not widespread. Eric found it on Bacon Rind and in Teepee Basin, while Mark and I could not find it around Lionhead. Two feet deep is another weak, thin layer of facets with sporadic distribution. This layer would require a heavy load to break, but with continued wind-loading today and more snow tonight, it's worth looking for.

I recommend staying off of wind-loaded terrain and digging for these buried layers. If you find them notch back the slope angles to be on the safe side. Weak layers are under the most stress during and immediately following storms.

For today, the Avalanche Danger is rated CONSIDERABLE on all wind-loaded terrain and MODERATE Avalanche Danger on all other slopes.

Heads up: Cornices have grown very large in recent weeks. These monster blocks of snow now severely overhang ridges. It's hard to know when or where they will break, but these tumbling blocks of dense snow are a hazard by themselves. Approach them with caution whether walking on a ridge or skiing or riding beneath them. Additionally, falling cornices make great triggers for avalanches.

Avalanche Video Clip from Utah

http://youtu.be/1ynAm5Wao1I?hd=1

This is a great clip of a snowmobiler triggering a slide on March 9th in the Uinta Mountains, Utah. He hurt his leg, trashed his machine, but should recover fine. Watching the clip a few things stand out:

1. Small slopes can be dangerous, especially when slides push you into trees.

2. His helmet cam shows how fast even a small slide accelerates.

3. Partners watching from a safe zone are worth their weight in gold.

PHOTOS, SNOWPITS, VIDEO and SURVEY RESULTS

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. The results from our survey are posted online. Thanks to all who participated. You can check out the results at http://bit.ly/fpLuSi.

In response to our survey we added a new page to the website with images of our snowpit profiles. This page is under the Resources/Other Info tab at http://fsavalanche.org/Encyclopedia/snowpit.htm

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.