Today...Breezy. Snow in the morning...then rain showers and snow showers in the afternoon. Snow accumulation of 1 to 3 inches. Highs 36°F to 42°F. Southwest winds 15 to 25 mph. Chance of precipitation near 100 percent.

Tonight...Breezy...cloudy. Snow showers likely in the evening... Then chance of snow after midnight. Snow accumulation around 1 inch. Lows 16°F to 22°F. Southwest winds 15 to 25 mph. Chance of snow 70 percent.

Tuesday...Breezy...cloudy. Slight chance of snow in the morning... Then rain and snow likely in the afternoon. Snow accumulation up to 1 inch. Highs 37°F to 43°F. Southwest winds 15 to 20 mph. Chance of precipitation 60 percent.

Tuesday Night...Breezy...snow. Snow accumulation of 2 to 5 inches. Lows 22°F to 28°F. Southwest winds 15 to 20 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 4 inches. Total snow accumulation 6 to 15 inches. Highs 35°F to 41°F. Southwest winds 15 to 20 mph. Chance of precipitation near 100 percent.

Wednesday Night...Colder. Cloudy with a 50 percent chance of snow. Lows 12°F to 18°F.

Thursday...Partly cloudy with a 30 percent chance of snow showers. Highs 27°F to 33°F.

Thursday Night...Partly cloudy with a 20 percent chance of snow showers. Lows 13°F to 19°F.

Friday...Partly cloudy. Slight chance of snow showers in the morning...then slight chance of rain showers and snow showers in the afternoon. Highs 33°F to 39°F. Chance of precipitation 20 percent.

Friday Night...Partly cloudy with a 20 percent chance of snow showers. Lows 15°F to 21°F.

Saturday...Mostly cloudy. Chance of snow showers in the morning... Then chance of snow showers and rain showers in the afternoon. Highs 33°F to 39°F. Chance of precipitation 50 percent.

Saturday Night...Mostly cloudy with a 40 percent chance of snow showers. Lows 15°F to 21°F.

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

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Mountain Weather

Warm and windy conditions are covering our forecast area. Currently, winds are blowing out of the WestSouthWest at 25-35 mph with gusts in Hyalite and Big Sky reaching over 50 mph. Mountain temperatures are currently in the high 20's Fahrenheit and will warm into the 30's Fahrenheit by this afternoon. Winds will continue to blow out of the WestSouthWest at 20-40 mph through the morning hours, but will gradually decrease by this evening. A weak weather disturbance will arrive by early afternoon depositing 2 to 3 inches of snow in the south and 1 to 2 inches in the north. A ridge of high pressure will build tonight into tomorrow making for a nice day on Tuesday.

Snowpack and Avalanche Discussion:

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

The snowpack throughout our advisory area is generally "right side up", meaning high density snow is making up the foundation of our pack which is supporting lower density snow near the surface. This type of staircase structure often indicates stability, which is what we are currently seeing in most areas. Although a high percentage of the snowpack is comprised of this structure, a few problem areas do exist.

The primary avalanche concern today will be freshly formed wind slabs which have grown over the past 12-18 hours due to increasing winds. Although warm and calm conditions over the past few days have helped to limit snow available for transport, enough snow has been moved around to create a potential hazard. Upper elevations slopes with a north and east component will be the most prone to slab development. Although freshly formed wind slabs will likely break less than a foot deep, the possibility of triggering a deeper, older slab does exist. A skier near Cooke City observed recent avalanche activity which probably occurred due to the snow and wind event of March 10-11. One avalanche was estimated at close to four feet deep. Trigging a pocket of fresh wind deposited snow could potentially step down to older wind slabs, producing larger and more dangerous avalanches.

A second concern is a layer of facets 2 feet below the surface which has been found in the southern Madison Range. I found this layer in Bacon Rind on Saturday and again in Teepee Basin yesterday. This layer propagated in stability tests, although it did take some force to initiate. I do not expect this layer to be a major problem unless it is on a slope with a heavy wind load. We have not found this layer outside of the southern Madison Range, but that does not mean it doesn't exist in other areas. Digging a snowpit and evaluating the strength and structure of the snowpack on the slope you plan to ride is always a healthy safety measure.

Today, continued strong winds will make human triggered avalanches possible on wind loaded slopes which have a MODERATE Avalanche Danger. Slopes that have not received a wind load have a LOW Avalanche Danger.

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.

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.