SOS Project researchers uses high quality digital kitchen scales, like those used to measure flour, to weigh snow. (European bakers understand that weighing flour is more precise than using measuring cups). The weight of snow is from the water content in the snow.
Number deployed on SOS Project: 2
Make/model used on SOS Project: Snowmetrics
This video shows the process of building a snow pit from start to finish, and shows the use of a snow scale (at 52 seconds). The weighing of snow provides insight into how much water is contained in the snowpack.