What Makes Up The Heat Index?

One thing we seem to despise in the spring (but would love to see now) is all that heat and humidity. We hate when it’s here and miss it when it’s gone.

There is one thing that we can all remember seeing during those hot and humid days: you wake up and check the weather for the day and see two different temperatures for the day. One says “temperature” and one says “heat index.” When we see the temperature at 90 degrees but a heat index of 105, which one is the true temperature for the day?

Well, this question was asked by George and Susan, and to tell you the truth, I didn’t know what the difference was either. The term heat index is just a fancy word for how the heat and humidity feel for the human body. Basically, it is used as a measurement to say what temperature your body thinks it is and how you should combat the double hit of heat and humidity. This scale works how you would think, the higher the number the hotter it feels, that’s why it’s also known as “feels like” in the winter, and the more dangerous it is to us, which is why you have to stay hydrated in the heat.

George and Susan also asked what effect the wind has on the temperature. Well, this affects us more now in the winter than ever. As we have seen this year, it seems like the temperature was being held behind a dam and finally released all at once. Instead of a gradual drop in temps, it came all at once with it dropping to the mid 20’s last week. Along with the sharp drop in temps came a blast of wind that seemed to drive the cold into your bones.

Here comes the other name for heat index: “feels like.” As much as it seems like the heat index only applies in high doses of humidity, it applies to all conditions of humidity.

Fun fact: if you want to get an idea of how humid it is outside without going outside you can look at the dew point. The closer it is to the actual temperature, the higher the relative humidity. Even if there is little to no humidity, the heat index still applies. In the winter with our lack of humidity, the heat index will plummet if there is anything over a 10 mph wind. If it’s hot and no humidity the wind will actually increase the heat index.

There is actually an awesome astronomical event on the docket for next week. On Sunday night/early Monday morning, the Dec. 13-14, there will be the best meteor shower of the year. The Geminid meteor shower will peak at 9-10 p.m. on Sunday with rates of over 100 meteors per hour.