Transcript for Heat wave continues to envelop half of US after storms hit Northeast
Now the major heat wave threatening a part of the country tonight. Many, this is the hottest fwhet years. The heat index, the feel-like readings, well over 10 and spreading. 107 in D.C. Tomorrow. 105 in philly. 1507 in philly. It will be warmer by Saturday. Tonight, authorities are warning this combination of heat and humidity could be life threatening. ABC's Alex Perez in Chicago. Reporter: Tonight, that heat wave sweltering more than half the country, after lightning packed deadly storms rocked the northeast. Torrential downpours turning new York's subways into waterfalls and sending thousands at this outdoor event scrambling for safety. In Connecticut, a lighting strike sending a large tree limb crashing onto a car. The driver rushed to the hospital. He did not survive. This as heat, humidity and stifling air smother much of the country. Feels like 108. 109, this is serious. Reporter: In Wichita, it felt like 108 degrees Wednesday, a bad day to be laying hot asphalt. When it gets hot out here like this, we take plenty of breaks. Reporter: Chicago roofer John weidel, facing long hours exposed to the sun. It can be a lot hotter up there with the sun beating down on us. Reporter: The city's mayor warning residents. These are life-threatening temperatures and conditions and we all have to work together to remain safe. Reporter: Even commuter trains ordered to slow down, to ease stress on the hot tracks. New York City bracing for 100 degree temperatures this weekend. After last weekend's blackout, officials say the grid will hold up. We've got over 4,000 crew members on the ground ready to respond to outages as they occur. Reporter: Tomorrow, tomorrow is supposed to be the hottest day of the year here. Feel-like temperatures of 110 degrees and the beginning, the oppressive heat expected to linger through the weekend. The cumulative effect is the most concerning. That Reese right. Alex Perez. The heat wave is just getting it will's get to ginger zee tonight. She is tracking it all. Ginger? Reporter: Good evening to you, David. We start, Hartford, Connecticut, Washington, D.C., places that have not seen 100 plus V plus degrees in three years. Philadelphia, New York City. It's been seven years. I think they are going to see the century mark this weekend. Look at the map there, a ridge of high pressure. The jet stream that acts as a fence to keep the cool air. It's so far north. Look at Lincoln, tomorrow afternoon, 110. Des Moines, Chicago, 107. The core of the hot air slides east and by Saturday, it settles N Richmond Virginia, 112, it feels like, the heat index in New York City and Philadelphia will approach 110. The lows could be the warmest we have seen in years, if not records. Ginger, thank you. Let's keep an eye on our neighbors throughout this. Amid the blistering heat, the
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