What is the difference between isolated showers and scattered showers?

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Dear Tom,
What is the difference between isolated showers and scattered showers?
— Bob Ciulla, Des Plaines
Dear Bob,
Meteorologists use the words “scattered” and “isolated” to describe the amount of area that is affected by random, disorganized showers or thunderstorms (or other specific weather events) at any given moment.
Scattered showers or thunderstorms are those whose area coverage at any instant is about 10-50 percent and whose occurrence across the landscape is random. That is, they display no organization such as lines or clusters, and they randomly cover 10-50 percent of the area.
Isolated showers or thunderstorms are loners, individual events well removed from any others and affecting less than about 5 percent of the area. You will often hear the terms “scattered” or “isolated” in weather forecasts in the summer, when the nature of showers and thunderstorms is, indeed, scattered or isolated.

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