With summer in full swing, you might have heard a lot about the heat index in the weather forecast. But what exactly is it, and why should we care? Let’s take a closer look.
What is the heat index?
Think of the heat index as your body’s personal weather report. It is not just about the temperature your thermometer reads, but how hot it feels when you factor in the humidity. When it is humid, your sweat does not evaporate as easily, which makes it harder for your body to cool down. That is why 90 degrees with high humidity feels worse than 90 degrees with dry heat.
Why does the heat index matter?
The heat index is not just about a lack of comfort. It is a serious health concern. That is why the National Weather Service has categorized the heat index into four levels, each with different effects on the body.
These categories help you gauge how much caution you need to take when spending time outdoors. If the heat index is in the “caution” or “extreme caution” range, you might want to adjust your activity level, seek shade, and stay hydrated. If it reaches “danger” or “extreme danger,” it is best to stay indoors, if possible, especially during the hottest parts of the day.