In weather and climate, the words "average" and "normal" are terribly misunderstood. An average is the mean over a period of time, usually the period of record. A normal is similar to average, except the data are smoothed to fit into a curve and the period of time covered is usually the most recent complete three decades. The problem is, many people have the idea that these averages and normals represent what the weather should be doing, which is not it at all.

Weather in general, and our climate in particular, is prone to extremes. It is almost always hotter, colder, wetter, or drier than average. Average is the average of all the extremes. When we get a warm spell like around Easter or a cold snap like the past few days, the weather is actually doing what is has always done, which is being something other than average.

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