If Eight Feet of Snow Instantly Melts, How Deep is the Puddle?

Things you think about while shoveling out more than a foot of snow. (Again.) How high can I consistently throw snow while shoveling? Will it clear the summit of Snow Planet, the mountainous pile next to my driveway? And if all this snow around me instantly melted, how much water would I be standing in?

Answers: 8 feet. No. And roughly half a foot.

The Boston region is currently buried under a monumental amount of snow. The snowpack is 3 to 4 feet deep. The sidewalks are like the Himalayas, with snowy shoveled peaks rising above hidden driveway canyons. With nearly 8 feet of snow falling in less than a month, and with little of that melting, there is a lot of frozen water blanketing the landscape.

It's easy to see how much by taking a look at NOAA's current snow water equivalent map, which models the estimated amount of liquid water contained in the snow. For much of eastern Massachusetts, the current map shows roughly half a foot.

NOAA's Snow Water Equivalent Forecast for February 17, 2015

All that got me thinking. My grandfather always told me that the rule of thumb for snow to water was 10 inches of snow per inch of water, which would mean something closer to 9 inches of water given the amount of snow (roughly 90 inches) that has fallen without any significant melting.

Turns out Grandpa was right. And wrong. The snow-water equivalent varies substantially with temperature, as this straightforward chart from NOAA shows.  Yes, if the temperature is around freezing, 10 inches of snow roughly equals an inch of water. But if the temperatures are 15 to 19 degrees, it's double that—1 inch of water generates 20 inches of snow. And so forth.

Given the cold nature of these insane February snows, clearly we've gotten a lot of depth per inch of water. And, oh yeah, 6 inches is still a lot of water. It's going to be a very wet and soggy spring this year. We'll see how long it takes to return Snow Planet to its watery origins.

Snowpack in Boston area: three to four feet. Unreal. 
 
Equipped” is an AMC Outdoors blog, written by Matt Heid.

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