Did you know that for much of the country the definite physician of a heat wave is three days of untrumtd heat. This is the time when hospitals say they begin to see people in trouble, sudden effects... See More
Did you know that for much of the country the definite physician of a heat wave is three days of untrumtd heat. This is the time when hospitals say they begin to see people in trouble, sudden effects on the human body, heart, blood pressure, also the brains of people of all ages. So what happens? Abc's meteorologist ginger zee is out tonight and she's going to show us what is happening all around the country. Reporter: Whether it's the 90s THAT FEEL LIKE 100 IN Chicago -- it feels like you're going to explode, it's so hot. Reporter: Or the whole feels like the inside of an oven. You can't just call any heat a heat wave. There is an actual definition for a heat wave here in the northeast. Three days at 90 or higher. We're on day four. Tell you what, these guys can tell you we've done it. Like a sauna probably. Reporter: He's been out there washing windows for the last five hours. Probably gone from the glass in your face. Reporter: The water evaporates before he can wipe the window clean. As the temperature on the glass approached 120, the whole team called it quits. It's hot like a trying pan. Reporter: The heat is taking its toll. On tuesday an intern at a conference in new york passed out. This man tested how hot it gets in a car. We approached 120 degrees in the car, completely miserable. Reporter: We asked dr. Jennifer ashton to measure what the heat does to the average person going about their day during a heat wave. This is stacey. She's in good health. Dr. Ashton took her blood, rate, heart rate and urine. I'm going to check that in the morning, check it in the afternoon, see how dehydrated you get. Reporter: Five hours later, after running every day errands like watering plants, doing laundry, she lost three pounds. Her heart rate went from a normal 72 to 127. Even her urine showed obvious signs of dehydration. Day after heat never allowing a person to cool down can be dangerous for a body. We expect to see people with heat exhaustion and heat stroke at the end of this heat wave than the beginning of it. Reporter: It's the ohios but the low lows. Washington d.C. Temperature didn't go low 80 degrees, a trend that won't break until sunday. Get this, allstate's in the lower 48 have hit 90 degrees for higher at least in someplace. That's a big wave of heat for much of the nation. It's going to break. I have some good news. That's the national temp I was telling you about. Look for places like chicago, the cooling will come not just for storms. Look at that, 80 degrees by the end of the week. Have to wait until the end of the weekend but that's going to come with severe storms. Diane? Thank you, ginger. The heat is compounded by the
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