Mark Twain is given credit for having said, "There are three kinds of lies: lies, damn lies, and statistics." He was referring to the use of statistics by politicians. Some things, apparently, never change. The line is also of value in reference to weather. Many people mistakenly think that "average" somehow shows what the weather is "supposed" to be or "usually" is. This is not so.
Weather, by its very nature, is variable. From day to day and from year to year, weather is inconsistent. In fact, weather is almost never average. For example, the average daily high in Fargo is 18 degrees in January. However, high temperatures are likely to vary from -10 to 35 degrees during the month. The "average" of any weather element is nothing more than the statistical mean. And that, Mr. Twain, is no lie.