The heat index, or also called the apparent temperature, it is a measure what the temperature feels like to the human body when relative humidity is combined with the air temperature.
The statement that it is important to know the heat index because it gives you a more realistic idea of the temperature your body will feel outdoors is true. There is direct relationship between the air temperature and relative humidity and the heat index. As the air temperature and relative humidity increase (decrease), the heat index increases (decreases).
