John Wheeler, WDAY, Published February 16 2013
Weather Talk: It’s difficult to forecast, measure snow preciselySnow is hard to forecast precisely. Varying cloud temperature and humidity produces differently shaped crystals, some of which accumulate more densely than others. Wind and melting can cause compaction, which affects accumulation. Sometimes snow partially melts as it accumulates, lowering the depth. This is why forecasting snow amount is at best an educated guess.
Once it has fallen, snow is also hard to measure accurately. If it is partially melting as it falls, the depths of new snow may vary on different surfaces. If it is windy, it can be very hard to estimate an average. A heavier snowfall will compact as it accumulates, and if it is windy, the drifting can produce hugely varied depths from place to place. One yard may average a foot or two more snow than another yard, depending on how the houses and trees affected the wind field. Old snow may get mixed in with the new, further muddling the situation. This is why measuring snow is at best an educated guess.
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