Warm and wet day at Armstrong Pass

Location Name: 
Armstrong Pass
Region: 
Luther Pass Area (including Job and Freel)
Date and time of observation: 
Tue, 04/11/2017 - 12:00
Location Map: 
United States
38° 49' 54.642" N, 119° 54' 46.9656" W
See map: Google Maps
US


Red Flags: 
Rapid warming
Observation made by: Professional Observer
Snowpit Observations
More detailed information about the snowpack: 

Greybird day and no good pictures to post:

Mix of rain and snow throughout the day from 8000ft to 9200ft, with more rain at 8000ft and more snow at 9200ft. No accumulation observed. Freel remained in cloud cover all day above about 9600ft. Consistent Moderate S winds were not observed to be transporting snow, likely due to Moist to Wet snow surfaces.

Sunny aspects held a breakable crust in the AM and softened to Wet by 11am. Shallow drainage runnels appearing on these slopes. Good bonding to previous rain crust observed on sunny aspects. Some previous Wet Loose activity observed near rocks on the steep SW aspect of Freel, but no current Wet Loose instability observed today.  

On shady aspects, snow surface was transitioning from Dry to Moist up to our high point of 9200ft. Snow in trees remains unconsolidated and rode well today. On more open slopes, snow was noticeably higher density from previous wind transport, but no cracking was observed with purposeful cuts on steep slopes, including stacking tracks progressively higher. Mitt pits showed gradual, "right side up" density changes to the previous rain crust down 50cm, with good bonding at this interface.

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
100% of the sky covered by clouds
Air temperature: 
Above Freezing
Wind Speed: 
Moderate
Precipitation: 
Mixed rain and snow
Air temperature trend: 
Warming
Wind Direction: 
South
Accumulation rate: 
None
More detailed information about the weather: