Rest Of Today...Snow likely. New snow accumulation of 1 to 2 inches. Total snow accumulation 1 to 4 inches. Highs 23°F to 29°F. West winds around 15 mph late in the afternoon. Chance of snow 70 percent.

Tonight...Cloudy with a 40 percent chance of snow. Lows 3°F to 11°F. West winds around 15 mph early in the evening.

Wednesday...Partly cloudy with a 20 percent chance of snow. Highs 21°F to 27°F.

Wednesday Night...Partly cloudy with slight chance of snow in the evening...then mostly cloudy with occasional flurries after midnight. Patchy fog after midnight. Lows 2°F to 8°F. Chance of snow 20 percent.

Thursday...Partly cloudy. Patchy fog in the morning. Occasional flurries in the afternoon. Highs 22°F to 28°F.

Thursday Night...Partly cloudy in the evening then becoming mostly cloudy. A 20 percent chance of snow. Lows 7°F to 13°F.

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

Friday Night...Partly cloudy with a 20 percent chance of snow. Lows 8°F to 14°F.

Saturday...Partly cloudy with a 20 percent chance of snow. Highs 26°F to 32°F.

Saturday Night...Mostly cloudy. Slight chance of snow in the evening...then chance of snow after midnight. Lows 6°F to 12°F. Chance of snow 40 percent.

Sunday...Partly cloudy with a 40 percent chance of snow. Highs 21°F to 27°F.

Sunday Night...Mostly cloudy in the evening then becoming partly cloudy. A 30 percent chance of snow. Lows 3°F to 9°F.

Monday ~ Washingtons Birthday...Mostly cloudy with a 50 percent chance of snow. Highs 21°F to 27°F.

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Mountain Weather

This morning 3 to 4 inches fell in the northern mountains and 2 to 3 inches down south with light westerly winds averaging 10-15 mph. Temperatures are in the teens Fahrenheit under cloudy skies. Scattered snow showers will drop another inch or two this morning. Under mostly cloudy skies mountain temperatures will rise into the 20s Fahrenheit with winds remaining light out of the west.

Snowpack and Avalanche Discussion:

The mountains around Cooke City:

Cooke City remains our problem child of the mountains. The couple inches of snow last night and a few more today will keep the slopes unstable. Some slopes have large grains of depth hoar underlying the entire snowpack. A fracture on this layer would produce large, deep, and destructive avalanches. Buried one to two feet deep on most slopes is another weak layer: small-grained facets that are not obvious. As you ski or snowmobile around today, remember these two things:

1. Remote Trigger. Two days ago skiers triggered an avalanche from far away. This is a sign of dangerous conditions since it tells us the weak layer is one continuous blanket connecting slopes together.

2. Repeat Offenders. Slopes are sliding for a second time on the foot thick layer of depth hoar. Previous avalanches shave a few inches off the weak layer leaving the bulk of facets to avalanche again. The steep and wide south face of Mount Abundance had a large natural avalanche a few days ago; eleven days after Eric triggered it. Similar aspects and elevations have similar snowpacks, so be extra careful around the south face and chutes of Scotch Bonnet too.

For today, the Avalanche Danger is rated CONSIDERABLE.

The Madison Range, southern Gallatin Range and the Lionhead area near West Yellowstone:

Faceted snow can be found on almost all slopes in the Madison and southern Gallatin Ranges and Lionhead area. To find it, you don't need a hand lens, just a shovel. The facets will crumble out of the pit wall as you dig. Although this snow structure is weak, without a rapid load of new snow the stability is good. Last night's three to four inches of fluff (.2 inches SWE) should not create natural avalanche activity. However, large facets on the ground along with layers of surface hoar and other small-grained facets in the upper two feet of the snowpack cannot be fully trusted. For today, it's still possible to trigger an avalanche and the Avalanche Danger is rated MODERATE.

The northern Gallatin Range and the Bridger Range:

The Bridger and northern Gallatin Ranges share a similar avalanche danger rating, but little else. The Bridgers are thin and weak. These mountains are not ready for the large dumps that must come someday. The northern Gallatins on the other hand, especially in the Hyalite area, are well nourished and fit. But its Achilles' heel is steep slopes, especially ones thin and rocky. On Saturday, a skier up Flanders drainage in Hyalite triggered a small slide when he jumped off a 3 to 4 foot rock band. He was caught, but not buried or injured. For today the Avalanche Danger remains MODERATE on slopes steeper than 35 degrees and a LOW Avalanche Danger on all other terrain.

NRCS Snowpack Summary Graphs:

For the current state of our snowpack depth (about 70% of average on the Gallatin), check out these two graphs generated by NRCS (graph 1, graph 2).

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.

Beacon Parks

The Friends of the Avalanche Center installed a Beacon Training Park outside West Yellowstone. It's located south of town on the main snowmobile trail. Stop by and do a quick practice before heading off into the mountains!

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.