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TUESDAY JANUARY 9 - SNOWFALL FORECASTS: THE NUMBERS GAME
With a big snowstorm in recent memory, I wanted to comment on one issue regarding
You've undoubtedly noticed that almost all forecasts of snow are given as a range
of numbers: for example, 2 to 4 inches, or 4 to 8 inches. A range is used partly
because of the uncertainty in forecasting snowfall amounts, and partly because
snowfall can vary widely over even a small area. If you get under a heavier band
of snow for a few hours and the town 20 miles down the road doesn't, you can easily
end up with considerably more snow.
Now about that range of snowfall amounts. Too often, people focus on just the
higher number. For example, a forecast of 6 to 12 inches might be remembered or
repeated as "up to a foot," and all of a sudden the lower limit of 6 inches is
lost in the shuffle. The fact is, the lower limit is just as likely to occur as
the upper limit - there's no reason to favor one over the other.