The Avalanche Warning issued December 15, 2016 is terminated. We will issue an advisory tomorrow morning, December 17, 2016 with current conditions.
High Danger
December 16, 2016
Avalanche Warning Terminated
Posted:
Dec 16, 2016 @ 5:25 pm
Problem 1 - Wind Slabs
-
TYPE
Wind Slabs
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.
-
SIZE
2 (Large)
The potential size of avalanche resulting from this problem.
-
LIKELIHOOD
Likely/Very Likely
The likelihood of an avalanche resulting from this problem.
Problem 2 - Persistent Slabs
-
TYPE
Persistent Slabs
Release of a cohesive layer of soft to hard snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Persistent, Deep-Slab.
-
SIZE
2-3 (Large)
The potential size of avalanche resulting from this problem.
-
LIKELIHOOD
Very Likely
The likelihood of an avalanche resulting from this problem.
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.
