and get ready for a nerve racking night on the nation's power grid. This unforgiving heat has already created power outages and already some people have been asked not to flip on that extra switch on... See More
and get ready for a nerve racking night on the nation's power grid. This unforgiving heat has already created power outages and already some people have been asked not to flip on that extra switch on the air conditioning. Officials warning that on this hot night we're all in it together. Abc's weather editor sam champion takes us around the country around. Reporter: It's day five of this heat wave and the effects of this relentless heat are taking their toll. The murkry hit 100 degrees in the new york city area, a record high for the day and officials are expecting the heaviest strain on power demand in history. I've been concerned all week. It's always not what is happening but what could happen. Reporter: If it's 100 degrees above ground, the temperature where the power lines are could be more than 120. To reduce stress on the system during peek times, officials are taking businesses to take steps like raising thermostats and shutting down elevators. All the lighting, motor, pumps, computers with all of that air conditioning rolling at the same time. Reporter: There have been outages today from washington to boston, amtrak putting speed restrictions on trains, worried the tracks may expand in this heat. The combination of high daytime temperatures and high nighttime temperatures to blame. In washington d.C. The it hasn't dropped below 80 degrees for more than 82 hours. In philadelphia workers had to add special chemicals to stop the concrete from drying so fast in this high heat. The heat is a concern for animals, too. At the chicago zoo, animals got a break with frozen snacks. Farmers concerned about heat stress on livestock now have an app for that. It measures the temperature and the humidity for annals and krounts the breaths for minutes. Daytime dinners temperatures at 93 degrees, heat index at 98 right here. The big question is everyone wants to know when does the heat break. Take a look at the cooler air around the great lakes. From the great lakes to the midwest strong thunderstorms will kick this heat into friday making it better on saturday. Look at the eastern seaboard and mid-atlantic. Until saturday and cooling it down sunday to monday, maybe a 20 degree difference from where you're sitting on friday. In south the heat wave rolls. The cold front doesn't reach you.
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