Now we move next and welcome to this week which is historically the hottest week of the year and tonight is off the charts thanks to the swal tering dome of heat sitting on ten states from michigan to... See More
Now we move next and welcome to this week which is historically the hottest week of the year and tonight is off the charts thanks to the swal tering dome of heat sitting on ten states from michigan to maryland. Ginger zee tracks down the people who are out in the hottest jobs. Reporter: Temperatures will be soaring above 100. You will be seeing the kids in the street, the nameless man on the street. The cliche shot of the sun. This week and next are the hottest of the year. What is the big deal? The big deal is heat kills an average of 119 people every year. Last year 1 55 people died because of heat, a majority were male and over the age of 55. Most were in homes without air conditioning. So we set out to see how quickly heat affects the human body. Now, my expertise ends when we talk about how hot it's going to get. What it does to a human body, i have no idea. So I brought in dr. Jennifer ashton. We tested sheila ash craft, a postal worker who works for five hours during the hottest part of the day. She la's heart rate is in the 120 which is consistent with kerz. Reporter: Another test you can do. Pinch this skin here. You're pretty well hydrated. We tall it tenting. If it skin doesn't snap back you could be dehydrated. If you can modify your activity to be more indoors than outdoors, do so. If you can take frequent breaks in cool environments and staying well hydrated. Reporter: Dr. Ashton told me if you are going tore outside for a long period of time in this week this week you have to have not just water but alternate with a sports drink. Just don't overdo it on the sugar. Ep them cooled. I have to show you how hot it's going to stay. New york city was 94 today. Look at these numbers for cities like new york city staying in THE 90s. Washington d.C. Peaks at 97 wednesday and 98 on thursday. Remember, it's not just the numbers, chicago, kansas city there. It's the feels like, too. It will feel above 100 for a lot of these folks for the next five days.
This transcript has been automatically generated and may not be 100% accurate.