How do we tell how much snow fell in a storm?

The monster “bomb cyclone” that hammered the US East Coast this week made it snow in places that are rarely coated in white: Savannah, Georgia got some 1.2 inches of snow, making records; while Charleston, South Carolina got 5.3 inches on January 3rd, the city’s third-snowiest day on record. So how is snowfall measured exactly? It’s trickier than you might think — and it’s still largely done manually with pretty rudimentary equipment.
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