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: Mostly sunny until late afternoon then becoming partly cloudy. Southwest winds around 15 mph. Highs 27°F to 33°F. Lowest wind chill readings -20°F to -30°F in the morning.

Tonight: Mostly clear in the evening then becoming partly cloudy. South winds around 15 mph. Lows 13°F to 19°F.

Wednesday: Breezy...cloudy. Chance of snow in the morning... Then snow...possibly mixed with rain in the afternoon. Snow accumulation of 1 to 2 inches. Southwest winds 15 to 20 mph. Chance of precipitation 60 percent. Highs 32°F to 38°F.

Wednesday Night: Breezy...cloudy. Snow likely in the evening... Then chance of snow after midnight. Snow accumulation of 1 to 2 inches. Total snow accumulation 2 to 4 inches. Southwest winds 15 to 20 mph. Chance of snow 60 percent. Lows 12°F to 18°F.

Thursday: Mostly cloudy with a 30 percent chance of snow. Southwest winds around 15 mph in the morning. Highs 28°F to 34°F.

Thursday Night: Mostly cloudy with a 40 percent chance of snow. Lows 13°F to 19°F.

Friday: Mostly cloudy with a 30 percent chance of snow. Highs 30°F to 36°F.

Friday Night: Partly cloudy with a 20 percent chance of snow. Lows 15°F to 21°F.

Saturday: Partly cloudy. Highs 30°F to 36°F.

Saturday Night: Partly cloudy. Lows 13°F to 19°F.

Sunday: Mostly sunny. Highs 32°F to 38°F.

Sunday Night: Mostly clear in the evening then becoming partly cloudy. Lows 13°F to 19°F.

Monday: Partly cloudy in the morning then becoming mostly cloudy. A 20 percent chance of snow. Highs 30°F to 36°F.

 Hazardous Weather Forecast  Yellowstone & Grand Teton Forecasts  Gibbon Falls Forecast  Mammoth Forecast  Midway Forecast  Norris Forecast  Old Faithful Forecast 

Mountain Weather

This morning under clear skies, mountain temperatures are in the single digits Fahrenheit with west to southwest winds averaging 10 to 15 mph. There's no new snow to report. Today will be mostly sunny with temperatures warming into the upper teens Fahrenheit and light southwest winds. This evening a Pacific low pressure system will bring cloudy skies and a chance of snow tomorrow.

Snowpack and Avalanche Discussion:

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

Yesterday, our main avalanche concern was on wind–loaded slopes. Northwest winds and 5 to 7 inches of snow created shallow drifts at the ridgelines. These drifts are still there and remain one of our avalanche concerns. They will not be very sensitive or large, but as Mark witnessed in Cooke City they have the potential to flush a person down unforgiving terrain (photo).

Throughout our advisory area faceted and weak layers of snow can be found in the upper three feet of the snowpack. These layers of concern vary from surface hoar to small, angular crystals. Stability tests quickly reveal them. On Sunday, in Dudley Creek in the northern Madison Range, Eric found a variety of faceted layers that were breaking in snowpits and causing him concern (video).

On some slopes the snowpack is shallow, weak and unsupportable. An unscientific, but valid test to find these slopes is to step onto the snow: sinking to the ground pinpoints a weak snow structure. These zones can be found on lower elevation slopes as well as rocky, wind-swept terrain above treeline (Hardscrabble avalanche pic). Last week, I found poor structure on Mount Ellis and Mark and Eric looked at a natural avalanche in thick trees on Mount Wheeler with a similar problem (photo). On Sunday, two snowboarders were caught in a small avalanche in the forest below the highest History Rock meadow in Hyalite (photo). I was unable to find the slide yesterday, but besides surfing over logs and head-faking tree branches I can attest to the thin and weak structure of the snowpack…in the trees.

Many slopes are stable, but some are not. The safest way to find the difference is to stop, dig and test the slope you plan on riding. So far we have been spared avalanche fatalities this season, but other regions have not. Last weekend a skier was killed in the Tetons as he climbed up a steep couloir (article) and a snowmobiler was killed in Utah on a slope with a snowpack very similar to ours (accident report). I mention this as a warning to not let our guard down. For today, the Avalanche Danger is rated MODERATE since it is still possible to trigger slides.

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.