Measuring snowfall by just sticking a yard stick in the ground seems inaccurate. How is snow accurately measured?
— R. Brod
We passed your question to Frank Wachowski, the Midway Airport observer, who has been measuring Chicago’s snow for more than 60 years. New snowfall is measured on a snow board — a 2-foot square piece of plywood painted white to reflect heat. The observer pushes a ruler down to the board’s surface and measures the depth of the snow to the nearest tenth of an inch. The board is cleaned off every six hours, with the summation of the six-hour totals providing the day’s official snowfall total. Snow depth is also recorded and measured to the nearest inch by averaging the depth of accumulated snow in as many as 10 sheltered locations, using locations where the effects of blowing and drifting are minimized.
New snowfall is measured on a snow board — a 2-foot square piece of plywood painted white to reflect heat.