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

Tonight...Partly cloudy. Lows -2°F to 6°F.

Sunday...Partly cloudy. Highs 23°F to 29°F.

Sunday Night...Partly cloudy in the evening then clearing. Patchy fog after midnight. Lows 6°F to 16°F.

Monday...Mostly sunny. Patchy fog in the morning. Highs 28°F to 34°F.

Monday Night...Mostly clear in the evening then becoming partly cloudy. Lows 10°F to 16°F.

Tuesday...Partly cloudy with slight chance of snow in the morning... Then mostly cloudy with chance of snow in the afternoon. Highs 26°F to 32°F. Chance of snow 30 percent.

Tuesday Night...Mostly cloudy with chance of snow in the evening... Then partly cloudy with slight chance of snow after midnight. Lows 4°F to 10°F. Chance of snow 30 percent.

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

Wednesday Night...Mostly clear. Lows 0°F to 10°F.

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

Thursday Night...Partly cloudy. Lows 2°F to 12°F.

Friday...Partly cloudy. Highs 26°F to 32°F.

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MOUNTAIN WEATHER

A dry cold front moving over southwest Montana is currently producing mountain temperatures in the low to mid teens Fahrenheit. Winds are blowing out of the West-northwest at 10-15 mph. Very little moisture is associated with this front, but a trace to one inch of snow is possible in the mountains by early afternoon. This front will exit the area by mid day allowing temperatures to rise into the high teens to low 20's Fahrenheit under partly cloudy skies. Winds will remain out of the West-northwest at 10-15 mph.

* AVALANCHE INCIDENTS *

Final reports on last weekend's avalanche accidents are available at: http://www.mtavalanche.com/accident

Snowpack and Avalanche Discussion:

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

It has now been a week since any measurable precipitation has fallen in southwest Montana. During this past week, warm and dry weather has helped last weekend's storm snow condense into a thick and supportable slab. This is making the snowpack less touchy, but stability assessment more difficult.

Signs of instability are becoming less obvious and avalanches are becoming harder to trigger but don't be fooled – a weak structure continues to produce a snowpack that should not be trusted.

Mark skied north of Bridger Bowl on Thursday and found the surface snow had been affected by recent warm temperatures but facets in the bottom half of the snowpack remained weak. Stability test scores indicated unstable conditions which was confirmed by numerous avalanches triggered by the Bridger Bowl Ski Patrol. Karl found similar conditions in the Lionhead area on Wednesday and a recent avalanche in the Taylor Fork was observed by snowmobilers on Thursday.

Today the Avalanche Danger is rated CONSIDERABLE. This means dangerous avalanche conditions exist, requiring careful snowpack evaluation, cautious route-finding and conservative decision making. See the complete danger scale below.

The northern Madison Range:

The mountains around Big Sky are caught between the more unstable conditions of the Bridger Range and southern mountains. Yesterday my partner and I toured into Beehive Basin and felt comfortable on slopes less than 35 degrees. However, unstable results during stability tests on multiple layers in the snowpack kept our decision making conservative.

With multiple persistent weak layers being capped by a cohesive slab 1 to 3 feet thick, human triggered avalanches remain likely on slopes steeper than 35 degrees where the Avalanche Danger is rated CONSIDERABLE. Slopes less than 35 degrees have a MODERATE Avalanche Danger.

The northern Gallatin Range:

Stability is better in the northern Gallatin Range. On Wednesday, my partners and I skied in Hyalite Canyon where we found facets near the ground in our snowpits but it took heavy force to make these facets reactive in stability tests. We also witnessed evidence of a sizeable cornice that broke and hit the slope below but did not trigger an avalanche.

Certain areas of the northern Gallatin Range have a layer of buried surface hoar, which Mark found on Mount Ellis. After discovering this layer, he opted not to ski steeper terrain.

The most likely areas to trigger a slide in the northern Gallatin Range will be in steep or rocky terrain where the snowpack is thinner. For today human triggered avalanches are possible and the Avalanche Danger is 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.

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.