An instrument that measures snow water equivalent by weighing the snowpack

Snow pillows measure snow water equivalent (SWE). Imagine a scale, like the one on which you weigh yourself at the gym or a doctor’s office, placed underneath the snow. Snow pillows record the change in mass during a storm, so they are extremely useful for measuring the load produced by a storm. During the spring melt, snow pillows quantify the rate of snowmelt.

A snow pillow being excavated mid-winter for repair. Credit: Natural Resources Conservation Service