Spring Conditions on Donner Summit

Location Name: 
Mt. Lincoln
Region: 
Donner Summit Area
Date and time of observation: 
Fri, 02/01/2013 - 12:00
Location Map: 
United States
39° 17' 0.6396" N, 120° 19' 34.1832" W
See map: Google Maps
US


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

Warm spring conditions on Donner Summit.  E-S aspects surface snow softened  by 11am and provided good soft corn snow conditions throughout the mid day.  South aspects has 2-3'' of soft snow on top of a firm, pencil hard crust that was boot and ski supportive.  East aspects had 2'' of soft snow on top of a firm, pencil hard crust that was 2'' thick.  Shaded aspects, N-NE, were firm all day and showed no signs of softening.  These aspects that were exposed to the past N-E wind events are firm and very rough with challenging travel conditions.  Very limited wet snow instabilities observed throughout the day.

 

Photo#1:  Refrozen, shiny snow surface on south aspects at 11am.

Photo#2:  East aspect, 7500' in protected treed terrain.  2'' of soft snow on top of a firm rain crust that was 2'' thick.  Below this crust was soft colder snow.

Photo#3:  Anderson/Lincoln Ridge.  N-NE aspects were very firm and did not soften much throughout the day, some patches of softer snow but that was limited.

Snowpack photos: 
Weather Observations
Blowing Snow: 
No
Cloud Cover: 
Clear
Air temperature: 
Above Freezing
Wind Speed: 
Calm
Precipitation: 
None
Air temperature trend: 
Warming
Wind Direction: 
South
Accumulation rate: 
None
More detailed information about the weather: 

Southside Mt. Lincoln, 7661', 11:20am.  Clear skies, calm SE wind, BootPen=10cm, SkiPen=0-5cm.  HS=175cm, ATemp +7c, Tsurf -.5c.

Upper Coldstream Canyon, East aspect meadow, 7520', 12:45pm.  Clear skies, no wind, BootPen10cm, SkiPen 5-10cm, HS=185cm, ATemp +6c, Tsurf -.5c