Today...Breezy. Cloudy with a 40 percent chance of snow. Highs 25°F to 31°F. Southwest winds 15 to 20 mph with gusts to around 35 mph.

Tonight...Breezy. Cloudy with a 50 percent chance of snow. Lows 12°F to 18°F. Southwest winds 15 to 20 mph with gusts to around 35 mph.

Monday...Breezy. Snow likely in the morning...then numerous snow showers in the afternoon. Snow accumulation of 2 to 3 inches. Highs 24°F to 30°F. Southwest winds 15 to 20 mph with gusts to around 35 mph. Chance of snow 70 percent.

Monday Night...Breezy. Numerous snow showers in the evening...then chance of snow after midnight. Snow accumulation of 2 to 3 inches. Total snow accumulation 4 to 6 inches. Lows 11°F to 17°F. Southwest winds 15 to 20 mph. Chance of snow 70 percent.

Tuesday...Breezy. Cloudy with a 40 percent chance of snow. Highs 23°F to 29°F. Southwest winds 15 to 20 mph.

Tuesday Night...Mostly cloudy with a 40 percent chance of snow. Lows 12°F to 18°F.

Wednesday...Mostly cloudy with a 50 percent chance of snow showers. Highs 24°F to 30°F.

Wednesday Night...Colder. Mostly cloudy with chance of snow showers in the evening...then partly cloudy with slight chance of snow showers after midnight. Lows 4°F to 10°F. Chance of snow 40 percent.

Thursday...Partly cloudy. Highs 24°F to 30°F.

Thursday Night...Mostly clear in the evening then becoming partly cloudy. Lows 2°F to 10°F.

Friday...Partly cloudy in the morning then clearing. Highs 30°F to 36°F.

Friday Night...Mostly clear. Lows 6°F to 16°F.

Saturday...Mostly sunny. Highs 31°F to 37°F.

 Hazardous Weather  Gibbon Falls Forecast  Mammoth Forecast  Midway Forecast  Norris Forecast  Old Faithful Forecast 

Mountain Weather

Strong winds continue to be the dominating weather factor throughout southwest Montana. Currently, winds are blowing are 25-35 mph out of the West-northwest with gusts reaching into the 60s at the Hyalite weather station. Mountain temperatures are in the low to mid 20s Fahrenheit around Bozeman and mid teens Fahrenheit near West Yellowstone and Cooke City. Today, winds will continue to blow 25-35 mph out of the West-northwest and temperatures will climb into the high 20s to low 30s Fahrenheit. Skies will remain mostly cloudy with a slight chance of snow showers over the mountains.

Snowpack and Avalanche Discussion:

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

The mountains near West Yellowstone have a snowpack structure similar to a lead safe balancing precariously on stacked wine glasses. This fragile balance will continue as long as a major disruption i.e. new snow, wind loading or a skier/snowmobiler does not facilitate additional stress.

The problem is - this snowpack structure is set up for failure. Unfortunately, every steep slope and any slope that has received a wind load will continue to produce avalanches under the weight of skier or rider. Now is not the time to forget that lower angle slopes connected to steeper slopes are considered avalanche terrain.

Weak layer distribution in the mountains around Cooke City is variable, making stability assessment tricky. The most persistent problem is occurring on southerly aspects where a layer of small grained facets buried 2 to 3 feet deep are resting over an ice crust. This layer has produced human triggered avalanches over the past week.

Making assessment even more challenging is the fact that many north facing slopes have a similar faceted layer, while other north facing slopes have a relatively strong and stable snowpack. On Friday, just south of Silver Gate, a natural avalanche was observed on a Northeast facing slope, a clear sign that unstable conditions persist.

Today, a cohesive slab 2 to 3 feet thick resting over various faceted layers make human triggered avalanches likely and the Avalanche Danger is rated CONSIDERABLE.

The Bridger Range and northern Madison Range:

Recent observations continue to indicate that the snowpack is gradually gaining strength. On Friday, skiers in Middle Basin found stable conditions on a Northeast facing slope and over the past few days the Big Sky Ski Patrol has continuously tested wind loaded terrain without results. These are both encouraging signs, but do not be fooled; the snowpack still has all the ingredients for producing an avalanche.

Today's primary avalanche concern will be wind loaded slopes. Over the past 5 days strong west winds have created dense wind drifts on lee side of exposed terrain features. Many of these drifts will be firm and supportable, making travel across them easy. This can provide a false sense of security. While hard and supportable slabs may feel stubborn and stable, they can still cut loose if hit in the right spot. Avoiding wind loaded slopes will be the best way to avoid triggering an avalanche.

While overall stability continues to improve, human triggered avalanches remain possible and the Avalanche Danger is rated MODERATE.

The northern Gallatin Range:

The northern Gallatin Range has the most stable snowpack in our forecast area. The limited distribution of a persistent weak layer and minimal snowfall over the past two weeks has made both natural and human triggered avalanches nearly non-existent.

Yesterday a skier on Mount Ellis found good skiing and stable conditions. A skier on Mount Blackmore found similar conditions on Thursday.

Although triggering an avalanche is less likely in this area, it is not out of the question. Isolated pockets of weak snow near the ground and recently formed wind drifts on steep-upper elevations slopes continue to make human triggered avalanches possible. For this reason the Avalanche Danger is rated MODERATE on wind loaded slopes and slopes steeper than 35 degrees. Less steep, non-wind loaded slopes have a LOW Avalanche Danger.

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.