The temperature is not the only thing that can impact how hot it feels outside — the amount of moisture in the air also makes a difference. The more moisture in the air, the hotter it will feel in the summer.
The heat index, or the "feels-like" temperature, is what it feels like to the body when humidity is combined with the heat.
The human body likes to stay at 98.6 degrees. Sometimes we get hotter internally, such as when we're working out, spending time in the hot sun or have a fever. When the body gets too hot, it sweats. The sweat evaporates from us and takes away the extra heat with it. Evaporation is a cooling process. But on a humid day, sweat is not able to evaporate from the body efficiently, and the body can't cool down as easily.
That is why meteorologists show the heat index along with the air temperature. It helps to tell the whole story.
The heat index is calculated by combining the air temperature with the relative humidity. You may not find the heat index on the thermometer, but it's an important factor during the summer months.
Be sure to practice heat safety and listen to your local meteorologists to understand the risks and impacts of the summer heat.
