Every year, tornadoes, lightning, hail, and flooding claim the lives of many across the United States, but none of those weather-related fatalities are as high as those that come from heat.

Over the last 30 years, fatalities from heat are the biggest weather killer not only across the United States but right here in our area across Northern Illinois. 

A July 1995 heat wave was one of the worst weather-related disasters in Illinois history according to the Illinois State Climatologist office. A major five-day heat wave hit areas across the Midwest and killed over 1000 people, 739 of them just in Chicago alone. This is more than a single tornado has killed anyone in history.

In the aftermath of the ‘95 heatwave, the Chicago National Weather Service office and the City of Chicago worked together to create better ways to prepare and enhance the warning communication for future events. There are now better protocols and policies for those who may not have easy access to cool off during extreme heat events.

So how is the temperature measured?  The official air temperature has to be taken in shade.  If it was measured in the sun, there would be a degree of variability depending on the different surfaces. Temperatures measured in the shade have more of a uniform number. While measuring in direct sunlight, temperatures can be at least 20 degrees warmer.

The heat index is what your body thinks the temperature is, because your body’s cooling system is not working properly. This is why it can be very dangerous to spend long hours in the sun/outdoors when it’s hot outside. The higher the dew point temperatures are, the more moisture is in the air and therefore our bodies are less effective at getting rid of the excess sweat and heat.

Typically during heat waves, nighttime temperatures often do not fall below the mid-70s and that prolonged heat has a big impact on our bodies.

If you have to spend a lot of time outdoors in the heat make sure to drink lots of fluids, even days leading up to the event, take breaks in the shade, and wear lighter colors of clothing. If you can’t get inside during a heatwave, make sure to keep an eye out for signs of heat exhaustion or a heat stroke in yourself and others.

A few signs of heat exhaustion include clammy skin, dizziness, excessive sweating. Signs of a heat stroke include an altered mental state, slurred speech, fast breathing/heartbeat and can cause a person to be hospitalized.

Submit your weather questions to weather@wtvo.com or sbrito@fox39.com and we will answer your questions on-air and on the web!