The NOAA website has a lot of historical information, but requires a certain amount of "drilling down" into the menus.
Here is some historical data for Aspendell,CA, near Bishop. Aspendell is at 9,000+ feet. By adding @ 5,000 feet you might be able to guess-t-mate conditions at the portal and summit of Whitney:http://www.wrh.noaa.gov/vef/climate/AspendellSnow.pdf
Looks like a complicated project!
I will try to find some historical snow pack data for you.
Ok...here is some data for the Big Horn Plateau (Kennedy Meadows area), which is south of Whitney: http://cdec.water.ca.gov/cgi-progs/snowQ...h=Retrieve+Datahttp://cdec.water.ca.gov/snow/current/snow/
First, the "Snow Course" menu will help you find the location of interest. Each area has a three-digit code, which is used for searches. The Snow Courses are areas of major water shed interest (drainages). The snow sensors and physical surveys are usually in meadows, not on mountain summits like Whitney.