Figuring the snow water equivalent is simply an exercise in determining its density - what does a certain volume of snow weigh? Light fluffy snow takes up a lot of space but doesn't weigh much. The corn snow, though it takes up less space, is generallly considerably heavier for the same volume.
This corn snow is also a sign that the pack is getting more dense and more susceptible to running off with elevated temps. and rainfall. I've attached a couple of links to track information on the current snow pack in the state. Pray (with me) for warmish days and freezing nights - the ideal cycle for melting the pack in a controlled manner.
NWS Snow Page
https://www.des.state.nh.us/exchweb/...%26js=1%26uc=0
NHDES Snow Page
http://www.des.state.nh.us/rti_home/...g_stations.asp