Observations West of Donner Summit

Location Name: 
Cisco Grove Area
Region: 
Donner Summit Area
Date and time of observation: 
Sat, 03/20/2010 - 11:00
Location Map: 
United States
39° 20' 26.772" N, 120° 32' 2.9616" W
See map: Google Maps
US


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

West of Donner Summit showing a good snowpack this spring, on N aspects at 7600' and 6600' HS > 240cm.  N aspects are still in transition at these elevations, a 2cm surface crust sometimes ski supportable and sometimes breakable.  E and S aspects have a well established  melt freeze crust, there was good radiational cooling last night with the clear skies that provided a good freeze.  This freeze was in open terrain and there was a noticeable difference in the trees where the crust was much weaker and softer.  At 5700' at 7:30 am AirTemp was -2.5c, at 7800' at 10:30am AirT was +2.5c.  Good corn skiing was at 10-11:30am on these solar aspects, moderate SW winds helped to keep things cooler at the higher elevations. Below 7000' by 12:30pm the snow was punchy and sticky on all aspects.

Weather Observations
Blowing Snow: 
No
Cloud Cover: 
50% of the sky covered by clouds
Air temperature: 
Below Freezing
Wind Speed: 
Moderate
Precipitation: 
Air temperature trend: 
Warming
Wind Direction: 
Southwest
Accumulation rate: 
More detailed information about the weather: