Buried weak layers.

Today we went into the Flathead Range to get a closer look at buried persistent weak layers and sus out any slab avalanches. 

• South aspects up to 7000 feet have a 1 to 2 inch crust that was 1 finger hard and softened considerably throughout the day. 
• We found two buried persistent weak layers within the top 1 to 2 feet of the snowpack on Northerly aspects.
  • The uppermost is a layer of buried near surface facets that formed during the 8th to the 10th with arctic air. These were buried on the 11th. 
  • The second is buried near surface facets just above the 3/4 AR rain crust (this is the very hard and slick crust). In some areas those facets are sandwhiched with another thin crust just above them. 
• We had unstable pit results (ECTP8) failing on the uppermost layer of near surface facets on a northeast aspect at 6600 feet. We found the same structure up to roughly 7000 which was our highpoint. 
• We had no obvious signs of instability. No cracking, no collapsing, and no whumpfing noises. One thing to note, almost all reported avalanches on Sunday did not experience those signs either.

Pictures later.