Today...Breezy. Partly cloudy. Highs 26°F to 32°F. Southwest winds 15 to 20 mph in the morning becoming southwest around 15 mph late in the afternoon.

Tonight...Partly cloudy. Lows 11°F to 17°F. Southwest winds around 15 mph early in the evening becoming southwest around 15 mph early in the morning.

Wednesday...Partly cloudy. Highs 29°F to 35°F. South winds around 15 mph early in the morning.

Wednesday Night...Mostly clear. Lows 13°F to 19°F. Southwest winds around 15 mph.

Thursday...Partly cloudy. A 20 percent chance of snow in the afternoon. Highs 30°F to 36°F. Southwest winds around 15 mph.

Thursday Night...Partly cloudy. Slight chance of snow in the evening...then chance of snow after midnight. Lows 10°F to 16°F. Chance of snow 30 percent.

Friday...Partly cloudy. Chance of snow in the morning...then slight chance of snow in the afternoon. Highs 18°F to 26°F. Chance of snow 30 percent.

Friday Night...Partly cloudy with a 20 percent chance of snow. Lows 4°F to 10°F.

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

Saturday Night...Partly cloudy. Lows 2°F to 10°F.

Sunday...Partly cloudy. Highs 21°F to 27°F.

Sunday Night...Mostly clear. Lows 4°F to 12°F.

Monday...Partly cloudy. Highs 22°F to 28°F.

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Mountain Weather

Yesterday was sunny and unseasonably warm with high temperatures in the Bridger Range reaching 45 Fahrenheit. Other mountain areas had temperatures in the high 20s to low thirties Fahrenheit. Winds blew hard out of the west to southwest with gusts hitting the 50s, but have lessened overnight and will die down even further this afternoon. Today will be more of the same: sunny and mild. This pattern of high pressure looks to stay with us through Thursday.

Snowpack and Avalanche Discussion:

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

The avalanche danger spiked on Saturday immediately after the storm. In two separate incidents a skier and snowmobiler were killed in avalanches near Cooke City. Further to the west, far outside our forecast area, a snowmobiler on Sunday was also killed in an avalanche east of Phillipsburg. With no new snow and minimal wind-loading, the snowpack is starting to stabilize as it adjusts to the new load. However, this is when stability assessment starts to get tricky. Avalanche activity and other obvious signs of instability are decreasing. Not all slopes are unstable, but a lot are. I'm more worried about human triggered slides this week than I was over the weekend. My advice is simple: Be conservative.

Yesterday Karl and I, plus two locals, investigated the avalanche that killed a backcountry skier on Saturday. The avalanche was triggered south of Cooke City up Hayden Creek. The slide was approximately 800 feet wide, 250 feet vertical with a crown depth averaging 1 to 3 feet deep and 35 degrees steepness. Although the crown was wide, the gulley that the skier was buried in was only 50 feet across. The avalanche broke on facets, some at the ground, others higher in the snowpack. I will have a detailed report later in the week, as will Eric on the fatality on Henderson Mountain. I posted a few photos on the web with more to come.

A lot of reports and observations are streaming into the avalanche center. Some relevant news:

1. Natural avalanches were seen again yesterday around Cooke City. We had some large, throaty, whumphs as we skied to the accident site yesterday. Eric's video from Sunday illustrates the touchy nature of the snowpack.
2. Lots of collapsing and cracking down south.
3. Very poor stability test scores were reported in the Bridger Range (ECTP 2, Q1).
4. Avalanches continue to release at the ground with explosives at Moonlight Basin.
5. Slopes that slid earlier in the year are getting reloaded and avalanching again. Fisher Peak outside Cooke City avalanched on Nov 26 an again yesterday. Compare the photos: Nov 26; Jan 2.

We are not out of the woods and should not let our guard down. Dangerous avalanche conditions exist and today the Avalanche Danger is rated CONSIDERABLE on all slopes in our advisory area.

Since yesterday morning we have posted more photos on the avalanche accidents, plus a few others relating to instability. More will be added today along with a video clip. Check these out at Photos and Videos.

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.

EVENTS, EDUCATION, 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.