Today...Mostly cloudy. Chance of snow in the morning...then slight chance of snow in the afternoon. Highs 17°F to 23°F. Southwest winds around 15 mph early in the morning becoming southwest around 15 mph in the afternoon. Chance of snow 40 percent. Lowest wind chill readings -17°F to -27°F in the morning.

Tonight...Mostly cloudy with a 20 percent chance of snow. Lows 3°F to 9°F. Southwest winds around 15 mph until early morning.

Friday...Mostly cloudy. Highs 22°F to 28°F.

Friday Night...Breezy. Mostly cloudy. Lows 8°F to 14°F. Southwest winds 15 to 20 mph.

Saturday...Breezy. Not as cold. Mostly cloudy in the morning then becoming partly cloudy. Highs 30°F to 36°F. Southwest winds 15 to 20 mph.

Saturday Night...Breezy. Partly cloudy in the evening then becoming mostly cloudy. A 20 percent chance of snow. Lows 15°F to 21°F.

Sunday...Mostly cloudy with a 40 percent chance of snow. Highs 27°F to 33°F.

Sunday Night...Partly cloudy with a 40 percent chance of snow. Lows 14°F to 20°F.

Monday...Partly cloudy with a 20 percent chance of snow. Highs 29°F to 35°F.

Monday Night...Partly cloudy. Lows 17°F to 23°F.

Tuesday...Partly cloudy in the morning then becoming mostly cloudy. A 20 percent chance of snow. Highs 29°F to 35°F.

Tuesday Night...Mostly cloudy with a 30 percent chance of snow. Lows 15°F to 21°F.

Wednesday...Mostly cloudy with a 40 percent chance of snow. Highs 27°F to 33°F.

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

Mountain Weather

With no temperature inversion this morning, it was colder in the mountains than in the valleys. Mountain temperatures were in the single digits Fahrenheit except near Cooke City and West Yellowstone where they were a few degrees below 0 Fahrenheit. Winds were blowing 15-30 mph from the West except in the Bridger Range where ridgetop winds were blowing 30-40 mph. Today a trace to 1 inch of snow should fall near Cooke City while all other areas will remain dry. High temperatures will be in the high teens to low 20s Fahrenheit and winds will continue unchanged.

Snowpack and Avalanche Discussion:

The Bridger and northern Gallatin Ranges:

In the past 48 hours strong winds blew the new snow (30 inches from the weekend) onto West aspects then back to East aspects by yesterday afternoon. This dramatic event was evident from Bozeman where we could see cornices in the Bridger Range facing town in the morning. By afternoon the same locations had been scoured to bare rock and the cornices were gone. This redistribution of snow is a red flag and a warning sign by itself.

Many slopes have a layer of small facets under the new snow. Doug and Eric found it on Mount Blackmore, and it produced an avalanche in the northern Bridger Range on Sunday. New snow plus strong winds plus a sensitive weak layer equals dangerous avalanche conditions. The key is to look for slopes unaffected by the wind without facets under the new snow.

Today the Avalanche Danger is rated CONSIDERABLE on all wind loaded slopes. On non wind loaded slopes, the combination of new snow and a sensitive weak layer makes human triggered avalanches very possible, and the Avalanche Danger on these slopes is rated MODERATE.

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

The mountains near Big Sky and Cooke City have a layer of facets under the new snow on some slopes, but it is not as widespread in these areas as we initially thought. Yesterday just south of Big Sky, Doug and I clocked over 40 miles on the snowmobiles trying to find this weak layer and map its distribution by frequently and quickly digging hand pits about 1.5 feet deep and testing small slopes and wind drifts. Our confidence in the snowpack gradually increased as we didn't find this weak layer and none of our test slopes cracked or moved.

Don't let your guard down because this layer of small facets can be found on specific slopes. Watch for slopes where this layer exists in combination with wind-blown snow which may be in unusual places. Near West Yellowstone this faceted layer is widespread, but it does not have enough new snow on top of it to be a major problem yet.

For today the Avalanche Danger is rated MODERATE.

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

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.

West Yellowstone: Beacon Park Operational

Skiing or riding near West Yellowstone? Test your beacon skills at a beacon park near the old airport where you can search for pre-placed beacons switched on/off by a control panel. Look for it by orange snow fence and signage just south of the snow cross track.

9th ANNUAL KING AND QUEEN OF THE RIDGE

The 9th Annual King and Queen of the Ridge will be held at Bridger Bowl on Saturday, February 12. ALL proceeds go to the Friends of the Avalanche Center who use the money to promote avalanche education in southwest Montana. Last winter we taught 64 classes reaching over 4,900 people. You can help raise money to continue this education in 2 ways:

1). Get pledges and hike the ridge. You don't have to do 20 laps – you can get flat pledges and hike just once! Or you can test your mettle and try and break John Yarington's record of 29 laps in 5 hours.

2). Sponsor someone. If you don't have someone to sponsor, consider sponsoring the GNFAC since we'll be hiking for dollars. Click Here for more information and registration forms.