There’s no doubt that these summer days in Texas have been HOT - but how hot are we talking? Why does it sometimes feel hotter than the forecast says it is?

Did you know that there is a difference between actual temperature and what is called the heat index? Understanding these two concepts is important in preparing for the weather! Let’s dive into it.

What is actual temperature?

The actual temperature, often indicated by a thermometer, measures the amount of heat present in the air. It is a straightforward measurement that tells us the level of hotness or coldness of the atmosphere. However, it doesn't take into account other crucial factors, such as humidity or wind chill, which significantly affect our perception of temperature.

WHAT IS THE HEAT INDEX?

Unlike the actual temperature, the heat index factors in the impact of humidity on our perception of heat. This index, calculated based on air temperature and relative humidity, provides a more accurate representation of how the weather feels. You can compute it through this online calculator, or refer to a heat index chart, such as the one below produced by the National Weather Service.

So, how does humidity affect our perception of heat? Well, our bodies regulate our body temperature through sweating, and high humidity impairs this process by slowing down the rate that our sweat evaporates, making the temperature feel hotter than it actually is. Even if the temperature is only 90 degrees, it can feel like a 100 if the humidity goes above 60%!

Wind chill during cold weather has the same principle; it speeds up the rate of heat loss which more quickly drives down internal body temperature. The air temperature could be 40 degrees outside, but with winds at 20 mph, it can feel 10 degrees colder!

Why is it important to understand the heat index?

Firstly, the heat index helps us assess the potential risks associated with prolonged exposure to hot weather. High heat index values indicate increased dangers of heat-related illnesses, such as heat exhaustion and heatstroke.

Moreover, the heat index is especially valuable for individuals engaged in outdoor activities or those working in hot environments. By considering both the actual temperature and the relative humidity, the heat index provides essential information to help people make informed decisions about their safety and well-being.

Choosing appropriate clothing, staying hydrated, and scheduling outdoor activities wisely become more critical when factoring in the heat index. It helps us understand the true impact of the weather on our bodies, allowing us to take necessary precautions and prevent heat-related health issues.

While the actual temperature provides a basic understanding of the heat in the air, the heat index offers a more comprehensive view by considering the influence of humidity. Recognizing the disparities between these two measurements equips us with valuable knowledge to better navigate the hot weather. So, in making your summer plans, don’t forget to watch the weather so you can safely enjoy the summer season!

If you’re visiting the Hill Country, consider making the Science Mill a stop in your travels! (The museum is nice and cool, we promise!) Only an hour from either Austin or San Antonio, the Science Mill is a family destination offering a fun, interactive learning environment for all ages. Through cutting-edge technology-based exhibits, games, and programs, the Science Mill expands students' understanding and appreciation of science in their everyday lives. By igniting their curiosity and inspiring them to pursue post-secondary education, the Science Mill experience starts students on the path to a life-long career in science, technology, engineering, and math (STEM).