Today...Chance of snow in the morning...then snow likely in the afternoon. Snow accumulation of 1 to 2 inches. Highs 23°F to 29°F. Southwest winds around 15 mph. Chance of snow 70 percent.

Tonight...Snow likely. Snow accumulation of 1 to 2 inches. Total snow accumulation 2 to 6 inches. Lows 5°F to 11°F. Chance of snow 70 percent.

Tuesday...Partly cloudy. A 20 percent chance of snow in the morning. Highs 22°F to 28°F. Southwest winds around 15 mph late in the afternoon.

Tuesday Night...Breezy. Mostly cloudy. Slight chance of snow in the evening...then chance of snow after midnight. Lows 10°F to 16°F. Southwest winds 15 to 20 mph. Chance of snow 30 percent.

Wednesday...Breezy. Cloudy with a 50 percent chance of snow. Highs 26°F to 32°F. Southwest winds 15 to 20 mph.

Wednesday Night...Mostly cloudy with a 50 percent chance of snow. Lows 18°F to 24°F.

Thursday...Cloudy with a 50 percent chance of snow. Highs 29°F to 35°F.

Thursday Night...Colder. Cloudy with a 50 percent chance of snow. Lows 10°F to 16°F.

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

Friday Night...Colder. Mostly clear. Lows 2°F to 8°F.

Saturday...Mostly sunny in the morning then becoming partly cloudy. Highs 22°F to 28°F.

Saturday Night...Partly cloudy. Lows 5°F to 11°F.

Sunday...Mostly cloudy with a 20 percent chance of snow. Highs 22°F to 28°F.

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Mountain Weather

Southwest Montana finally got a break in the weather yesterday as a weak ridge of high pressure built over the area. The ridge is beginning to break down this morning making for a change in the weather today and tonight. Currently, mountain temperatures are ranging from 10°F to 20°F and winds are blowing predominately out of West-southwest at 15-30 mph. Today, mountain temperatures will warm into the mid to upper 20s Fahrenheit and winds will continue at 15-30 mph out of the West-southwest. Snow will develop over the mountains today as pacific moisture moves into the area. 2 to 4 inches is possible in the southern mountains an 1 to 2 inches will likely fall in the north by tomorrow morning.

Snowpack and Avalanche Discussion:

The Southern Madison Range, Lionhead area near West Yellowstone and mountains around Cooke City:

Yesterday's calm weather allowed the snowpack to take a deep breath and start adjusting to last week's storm snow. This has helped overall stability. However, the pack is still far from achieving equilibrium.

The most recent storm deposited 3 to 4 inches of SWE, which fell on a very weak foundation of faceted snow. This weak layer is widespread in the mountains around West Yellowstone and is found on many slopes in the mountains around Cooke City. On Saturday, Mark observed a large natural avalanche on Scotch Bonnet which failed on facets formed prior to this latest storm. Yesterday, riders in the Lionhead remotely triggered two avalanches on wind loaded slopes, a poignant reminder of the unstable conditions that exist in that area.

The avalanche hazard is trending down, but human triggered avalanches remain likely today and the Avalanche Dangeris rated CONSIDERABLE.

The Bridger Range:

The Bridgers have the least amount of snow out of any range in our forecast area. This has allowed the snowpack to remain shallow and weak, producing a fragile foundation for any significant load.

Over the past few days, 8 inches of dense snow totaling close to 1 inch of SWE gave the snowpack its first real test in weeks. This fast and heavy load produced natural avalanches near Sacagawea and continues to stress the weak faceted layer near the ground.

Yesterday, my partner and I toured into the Flatirons north of Ross Peak and found a snowpack that was not trustworthy. A thick slab resting over weak facets created cracking and collapsing and produced unstable results in stability tests.

A weak structure and recent load make human triggered avalanches likely, specifically on wind loaded slopes which have a CONSIDERABLE Avalanche Danger. Non-wind loaded slopes have a MODERATE Avalanche Danger.

The northern Madison Range and Gallatin Ranges:

Yesterday, Doug and his partner traveled to Beehive Basin in the northern Madison Range and were encouraged by the overall stability of the area. This came as bit of a surprise, since I found unstable conditions in the same zone on Friday.

This means the avalanche danger spiked during the storm, but like a well trained athlete – recovered very quickly.

Skiers in the northern Gallatin Range also found good stability on Mount Wheeler.

Today's primary avalanche concern will be wind loaded slopes. Wind pillows beneath ridgelines, shallow rocky areas and slope convexities will be likely trigger points and should be avoided.

Today, heightened avalanche conditions exist on specific terrain features and the Avalanche Danger is rated MODERATE.

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 last Friday. 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.