Caution advised for snow falling off of building roofs. Park accordingly.

Dangerous avalanche conditions may already exist in many back country areas, please call the Recorded Avalanche Advisory 406-587-6981 for the most current conditions. Also, see the Avalanche Advisory posted below.

Today: Breezy. Chance of snow in the morning. Snow late in the morning. Rain likely late in the afternoon. Snow accumulation of 1 to 3 inches. Highs 31 to 37. South winds 15 to 20 mph in the late morning and afternoon. Chance of precipitation 90 percent.

Tonight: Cloudy. Snow in the evening...then chance of snow after midnight. Snow accumulation of 1 to 2 inches. Total snow accumulation 2 to 5 inches. Lows 13 to 19. Southwest winds around 15 mph. Chance of snow 90 percent.

Thursday: Mostly cloudy with a 40 percent chance of snow. Highs 28 to 34. Southwest winds around 15 mph until late afternoon.

Thursday Night: Cloudy with a 40 percent chance of snow. Lows 13 to 19.

Friday: Cloudy with a 40 percent chance of snow. Highs 29 to 35.

Friday Night: Mostly cloudy with a 30 percent chance of snow. Lows 14 to 20.

Saturday: Partly cloudy. Highs 24 to 30.

Saturday Night: Partly cloudy. Lows 14 to 20.

Sunday: Not as cold. Mostly sunny in the morning then becoming partly cloudy. A 20 percent chance of snow. Highs 32 to 38.

Sunday Night: Partly cloudy with a 20 percent chance of snow. Lows 13 to 19.

Monday: Partly cloudy in the morning then becoming mostly cloudy. A 30 percent chance of snow. Highs 30 to 36.

Monday Night: Mostly cloudy in the evening then becoming partly cloudy. A 30 percent chance of snow. Lows 15 to 21.

Tuesday: Mostly cloudy with a 30 percent chance of snow. Highs 28 to 34.

All Temperatures (Highs and Lows) are in degrees Fahrenheit (°F). All Sub Zero Temperatures are Highlighted.

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Mountain Weather

This morning, under partly cloudy skies, mountain temperatures are 20 degrees Fahrenheit with light southwest winds averaging 10 to 15 mph. The weather station at Lulu Pass outside Cooke City is windier with gusts reading 35 mph. Today a slow moving low pressure system will increase cloud cover and drop temperatures into the teens Fahrenheit this evening. Winds will remain light and by tomorrow morning 1 to 2 inches will fall around Lionhead and Cooke City.

Snowpack and Avalanche Discussion:

Bridger, Gallatin, and Madison Ranges, Lionhead Area near West Yellowstone, and Cooke City:

The past two days of no snow and light wind are helping the snowpack strengthen and stabilize. Although weak layers can form at the surface within hours, once buried they can take weeks or even months to gain strength. Today, we have three problems to look for which are all found in the top three feet of the snowpack.

1. Thin wind drifts formed this weekend, most noticeable around Cooke City. Some were triggered by skiers (photo) while others avalanched naturally (photo). Although not large, they are still capable of pushing a person into deadly terrain traps.

2. Shallow snowpacks (about three feet deep or less) are weak and unsupportable. This alone is not alarming, but on some slopes it is capped by a thicker slab and can avalanche. Snowboarders triggered a small slide in the forest by History Rock on Sunday and we investigated a similar slide on Mount Wheeler last week. A poor snowpack structure is also found on thin, rocky terrain above treeline which was responsible for the natural avalanche late last week on Hardscrabble in the Bridger Range. Photos of all three slides are here.

3. Weak layers of faceted snow or buried surface hoar can be found in all ranges, but not on all slopes. These layers are only a few millimeters to a centimeter thick and might not be visible in a snowpit wall, but they can be found with a stability test (video).

Snow stability assessment is all about gathering information about the area you plan on riding or skiing. Sometimes we get advanced warning the snowpack is unstable through a collapse or whumph; bulls-eye data that slopes are dangerous. In this case digging a snowpit is unnecessary. But most times digging is the only way to ensure these layers are absent or not an issue. Given our three points of concern, triggering avalanches are still possible and the Avalanche Danger is rated MODERATE.

The next advisory tomorrow morning at 7:30 AM. If you have any snowpack or avalanche observations, drop us a line at mtavalanche@gmail.com or call us at: 406-587-6984.

EDUCATION, PHOTOS, SNOWPITS, and VIDEOS

1. For links to Articles, Education and (photos), (snowpits), or (videos) listed in the above report, please visit this Link.

2. They have recently uploaded more photos and snowpits to their web site, more than what are linked in the advisory above.

3. They have creating a series of "How To…" stability test videos. So far they have clips on performing a CT and ECT. They are located under Stability Tests on their Resources page.

Information provided by Doug Chabot, Mark Staples, and Eric Knoff from the Gallatin National Forest Avalanche Center. For 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.