Good Morning. This is Eric Knoff with the 130th and last daily avalanche advisory of the season issued on Sunday, April 10th at 7:00 a.m. Today’s advisory is dedicated to everyone who supported our operation by reading the advisories; taking an avalanche class; donating money, time or gear; or sending in a backcountry observation. Our success is directly related to community support and the Forest Service. Thank you for 26 great seasons. This advisory does not apply to operating ski areas.
This morning mountain temperatures are in the 30s F under mostly cloudy skies and winds are blowing 5-20 mph out of the west. Today, a weak cold front pushing down from the north will keep temperatures ten degrees cooler than yesterday. Highs will only reach the low to mid 40s F and winds will continue to blow 5-20 mph out of the west. Skies will remain mostly cloudy through the day, but no rain or snow is expected. A ridge of high pressure builds tomorrow producing a warm and sunny start to the week.
Bridger Range Madison Range Gallatin Range
Lionhead area near West Yellowstone Cooke City
The snowpack is in transition. On all but upper elevation, north facing slopes the pack has started to move towards a wetter, more spring like snowpack. Over the past three days, every Snotel site in our advisory area has lost SWE (snow water equivalent), which means free moving water is migrating through the pack.
During this transition period, it’s not uncommon for the snowpack to become increasingly unstable. Yesterday, I skied in Beehive Basin and observed a few recent avalanches (photo). However, I was pleasantly surprised at how well the snowpack has been holding up to the prolonged period of above average temperatures.
Today, cloudy skies and cooler temps will help limit wet snow avalanches. It is worth noting that free moving water is still migrating through the pack, which can cause unstable conditions in specific areas. Places to look out for and avoid will be steep, rocky terrain where the snowpack is shallower and weaker (photo, photo). Also, if you’re sinking into soft-slushy snow past your boot top, it’s best to avoid steep terrain or move to shadier aspects.
Cornices: Cornices have grown enormous this season and continue to loose strength with the extended warm spell. They can break with a passing skier or fail naturally and deserve a wide berth along the ridgelines. Slopes below large cornices should also be avoided (photo, photo).
Today, the avalanche danger will start out LOW but rise to MODERATE as temperatures warm.
For more spring snow travel advice see a recent article that Alex posted on our blog page, article.
If conditions warrant we will issue intermittent avalanche information. If you have any snowpack or avalanche observations drop us a line at mtavalanche@gmail.com or call us at 587-6984