As new weather information continues to come in, it is clear that the heat is not going to back off. In fact, the heat and humidity may be slightly higher than previously thought! Heat index values will likely reach 100-108° Friday and 105-115° Saturday. For that reason, the National Weather Service has continued to place all of Michiana under an Excessive Heat Watch for the first time in seven years! That puts everyone in the "danger" category, especially Saturday. Sunstroke, heat cramps and heat exhaustion are highly likely for those who spend any significant amount of time outdoors. The risk of heat stroke, which is an emergency situation, will be elevated.
The actual temperature will soar to 96°, if not higher, by late Saturday afternoon. If that happens, it will be the first time South Bend has recorded an air temperature that high since September 11, 2013! In this kind of heat, nobody is "safe" from heat-related illness. Even those who are used to working strenuously in the heat and humidity will be highly susceptible to heat-related issues.
Many times you may not even notice that a form of heat-related illness is setting in. That is why the heat, which kills hundreds of people every year in the United States, is sometimes referred to as the "silent weather killer." The heat becomes far more dangerous when paired with extremely high humidity values because it essentially eliminates the body's ability to perspire and cool itself off. If you plan on being outside this weekend, sweat rates of one to two quarts per hour are likely.
That means you will need to drink four bottles of water, or as many as eight glasses of water, per hour to keep up with the amount of sweating you will be doing each day this weekend. If you don't keep up with your sweat rate, heat-related illness and/or organ dysfunction could ensue in only a matter of minutes. That is especially true if you plan on engaging in any sort of exercise or physical activity while outdoors.
In addition to drinking plenty of water, consuming light and small meals will be very important. Avoiding alcohol and making sure you have a way to cool off if necessary will also be good ideas through the weekend. Unfortunately, the heat likely sticks with us through the middle of July. While our heat indices won't be exceeding 105° every day, it looks like it will stay hot and muggy beyond this weekend.