Demystifying the heat index

With the return of exceptionally high temperatures this week, you will hear numerous references to the heat index. But what the heck does it really mean?
    Sometimes called the “apparent temperature” or “feels like temperature,” the heat index is a measure of how hot it feels. This is determined by adding the relative humidity to the actual air temperature and then applying a formula.
    For example, at the time this article was written, the air temperature was 86°, and the relative humidity was 62 percent. The heat index was 92°. In other words, though it was 86°, the relative humidity made it feel like 92°. You can determine the heat index by going to a National Weather Service website (

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