The predicted temperatures during the heat wave this weekend will tell only part of the story – it will feel much hotter. According to CNN meteorologist Dave Hennen, the population of the 48 will see temperatures above 90 ° F and more than half will see temperatures above 95 ° F.
But more important is the heat index
What is the heat index : It is also called "visible temperature". It's a combination of temperature and humidity, and measures what the body actually feels, CNN's meteorologist Haley Brink said.
For example, in Chicago – with an estimated Friday Friday of 98 degrees Fahrenheit and a relative humidity of 58% –
The Heat Index can become even taller when you think about what it feels like in the sun.
In "direct sunlight, the value of the heat index may be increased by up to 15 degrees Fahrenheit," according to the National Meteorological Service.
Brink said: The best way to stay safe in the heat is to drink plenty of water, to wear light, light clothes and to stay near the air conditioner.