The Unexpectedly Important Truth About Snow Measurement
The minute winter arrives, my kids are dying to put on their snow boots to go sledding and build snowmen. That is, as soon as we get snow. Just a couple of inches is all we need to have fun. One glance outside at falling flakes and we’re strapping on the knit hats, galoshes, and snow pants. But meteorologists know that to really measure snow, you need much more sophisticated equipment.
Snow measurement may seem seem banal, but it’s actually a very important forecasting indicator, vital to helping people and businesses prepare and plan for the months ahead.
A bountiful snowpack in the mountains will lead to spring snowmelt that brings fresh water to reservoirs and plenty of summer-fun splashing in full swimming pools and lawn sprinklers. Low snowpack will bring the opposite: diminished reservoirs and the threat of water restrictions, from car washing and sprinkler bans to rationing and, at worst, fines and temporary shutdowns of water-sensitive businesses. A good water manager can use snow measurement to avert hardships due to water shortages by promoting conservation in advance.
To accurately gauge the impact of snowfall, you measure the water content of the snow, not the height it reaches in inches.
This is done with a real snow gauge, which is much more precise than the fancy yardstick you might buy at the gardening center to look pretty in the backyard.
Snow gauges suffer from the same challenge that rain gauges do: If wind is strong enough, snow will blow past the opening of the gauge, and snowfall may be under reported.
So a real snow gauge is made of two parts—a copper catchment container and the funnel-shaped gauge at top. That funnel shape helps to minimize the snow drift/blow challenge by catching snow that may go wayward in the wind.
Once the snow collects in the catchment container, the container is switched out for a replacement and the snow is melted. It’s then poured out and measured in millimeters to reveal its water content. That’s what they mean by “wet snow” and “dry snow.”
All I know is that you can make much better snowballs with the wet snow. And though I’m grateful there are meteorologists out there with real snow gauges keeping my city water manager abreast of snow measurements and the conditions we’ll have this coming spring and summer, all my kids and I want is to see a big pile leaned up against a fancy yardstick in the backyard. Bring on the snowmen!
For more on winter maintenance, consider: