Above Leavitt Creek

Location Name: 
Above Leavitt Creek
Region: 
BWRA
Date and time of observation: 
Fri, 04/28/2017 - 15:00
Location Map: 


Red Flags: 
Whumphing noises, shooting cracks, or collapsing

Observation made by: Avalanche Specialist
Snowpit Observations
More detailed information about the snowpack: 

We are transitioning to a Spring-time snowpack. Thawing during the day with temperatures in the 40s, & freezing at night with temperatures in the low 20s & briefly into the teens. The layers of the snowpacks are warming to near freezing (isothermal) & moisture from daytime thawing is percolating through the pack on the path of least resistance. Fridays afternoon conditions were mostly stable with some localized whumphing of the top crusty surface(9inches). This is still a sign of instability & should be considered a hazard on slopes steeper than 35 degrees. Large temperature changes(& vapor pressure gradient) will cause faceting of round snow grains during cold nights, & will change the physical character of the grains. The faceting process will transform a round, dense grain, into a pyramid-shaped hollow cone with only the points touching. This allows for maximum airspace & promotes collapse & crack propigation throughout the snowpack.

Snowpit or crown profile photo or graph: 
Snowpack photos: 
Thickness
Delicate Decomposition
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
25% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Light
Precipitation: 
None
Air temperature trend: 
Static
Wind Direction: 
West
Accumulation rate: 
None
More detailed information about the weather: 

A High Pressure ridge is building bringing clear skies with warm days & cool nights.