An avalanche warning is in effect for the mountains of west central Montana above 6000 feet. The Avalanche danger is High on all wind loaded terrain steeper than 30 degrees.
Good afternoon! This is Steve Karkanen with this special warning from the West Central Montana Avalanche Center. We are still in the field and will post more info by Monday morning.
Release of a cohesive layer of snow (a slab) formed by the wind. Wind typically erodes snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
The potential size of avalanche resulting from this problem.
The likelihood of an avalanche resulting from this problem.
There is an increased risk of avalanches on these slopes:
N - North
NE - Northeast
E - East
SE - Southeast
S - South
SW - Southwest
NW - Northwest
Fresh wind slabs are very sensitive. We remotely triggered wind slabs in the Rattlesnakes and we received several good reports of sensitive snow in the entire Bitterrroot range this am.
Release of a soft cohesive layer (a slab) of new snow which breaks within the storm snow or on the old snow surface. Storm-slab problems typically last between a few hours and few days. Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
The potential size of avalanche resulting from this problem.
The likelihood of an avalanche resulting from this problem.
There is an increased risk of avalanches on these slopes:
N - North
NE - Northeast
E - East
SE - Southeast
S - South
SW - Southwest
W - West
NW - Northwest
Heavy new snow is failing easily on the old snow surface. In some areas, A thin facet layer formed on the snow surface during the dry weather last week.
This information is the sole responsibility of the Forest Service and does not apply to operating ski areas. The avalanche danger rating expires at midnight tonight but the information can help you make a more informed decision regarding travel in avalanche terrain for the next few days.
Our advisory area includes National Forest System lands in the Bitterroot Mountains from Lost Trail Pass north to Granite Pass, the Rattlesnake Mountains north of Missoula and the Southern Swan and Mission Mountains near Seeley Lake, MT. Avalanche information for the Lookout Pass/St. Regis Basin area is available from the Idaho Panhandle Avalanche Center.
