Today...Windy...snow. Snow accumulation of 3 to 5 inches. Highs 17°F to 23°F. Southwest winds 25 to 35 mph with gusts to around 55 mph. Chance of snow near 100 percent. Lowest wind chill readings -15°F to -25°F in the morning.

Tonight...Windy...snow. Snow accumulation of 3 to 6 inches. Lows 10°F to 16°F. Southwest winds 25 to 35 mph with gusts to around 55 mph. Chance of snow near 100 percent.

Thursday...Windy. Not as cold. Snow. Snow accumulation of 3 to 7 inches. Highs 25°F to 31°F. Southwest winds 20 to 30 mph with gusts to around 45 mph. Chance of snow near 100 percent.

Thursday Night...Windy...snow. Snow accumulation of 3 to 7 inches. Lows 14°F to 20°F. Southwest winds 25 to 30 mph with gusts to around 45 mph decreasing to 15 to 25 mph after midnight. Chance of snow near 100 percent.

Friday...Snow likely. Snow accumulation of 3 to 5 inches. Highs 26°F to 32°F. Southwest winds around 15 mph. Chance of snow 70 percent.

Friday Night...Snow likely in the evening...then chance of snow after midnight. Moderate snow accumulations. Lows 15°F to 21°F. Chance of snow 70 percent.

Saturday...Snow likely. Moderate snow accumulations. Highs 26°F to 32°F. Chance of snow 70 percent.

Saturday Night...Mostly cloudy with a 50 percent chance of snow. Lows 10°F to 16°F.

Sunday...Mostly cloudy with a 50 percent chance of snow. Highs 22°F to 28°F.

Sunday Night...Mostly cloudy with a 50 percent chance of snow. Lows 6°F to 12°F.

Monday...Mostly cloudy with a 40 percent chance of snow. Highs 22°F to 28°F.

Monday Night...Mostly cloudy with a 40 percent chance of snow. Lows 4°F to 10°F.

Tuesday...Mostly cloudy with a 40 percent chance of snow. Highs 20°F to 26°F.

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Mountain Weather

Mountain temperatures are in the high single digits Fahrenheit and winds are averaging 30-40 mph out of the west to southwest with gusts ripping to 70 mph. Cooke City has seven inches of new snow with Taylor Fork and West Yellowstone showing two inches. Today, winds will decrease, but still blow strong with temperatures rising into the teens. Snowfall will pick up later today and by tomorrow morning I expect 2 to 4 inches in the northern mountains and 6 to 8 inches in the southern zones. Tomorrow looks to be snowy too.

Snowpack and Avalanche Discussion:

The mountains around Cooke City:

There are two basic truths about Cooke City: it snows and it's windy. Seven inches fell with winds tearing across the mountains and through the valleys. The anemometer on Lulu Pass is showing a north direction, but I'm guessing the 30-60 mph winds are swirling around the compass. It would be hard to find a slope not affected by the wind. Wind-loaded slopes might avalanche naturally today, especially as drifts continue to grow. Slides may break at the old snow surface, but step down into weaker layers of facets. Be aware that slopes that avalanched during the New Years Eve cycle could avalanche again with this new load. For today, the Avalanche Danger is rated CONSIDERABLE on all wind-loaded slopes and a MODERATE Avalanche Danger elsewhere.

The Bridger, Madison and Gallatin Ranges, the Lionhead area near West Yellowstone:

Late yesterday the Bridger and Big Sky ski patrols mentioned that winds were loading slopes creating "thin, zippy wind slabs" about six inches deep. The Bridgers did not get snow in the last 24 hours, but they had nine inches by Monday morning that blew to the west side of the range and now is blown back to the east. All this movement creates very small grains that pack densely together into hard slabs. Winds have been powerful and new snow will feed the wind drifts. From the Bridger Range to West Yellowstone, with the exception being the Hyalite drainage, the snowpack has many layers of weak, faceted snow. I found this on Monday north of Bridger Bowl and yesterday on Buck Ridge south of Big Sky where, stepping off my sled, I sank to the ground. Eric's photo from this area on Friday shows the weak snow structure which will be unable to support a thick slab of snow.

So far there's been lots of wind, but not much snow. Slabs will be thin, but sensitive to triggering on steep slopes. For today, the Avalanche Danger is rated CONSIDERABLE on all slopes with a wind-load that are steeper than 35 degrees. All other slopes have a MODERATE Avalanche Danger. The avalanche danger will rise if we get the expected snows. As slabs continue to build from wind-loading it will become easier to trigger avalanches.

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.