AD Quality Auto 360p 720p 1080p Top articles1/5READ MOREFrumpy Middle-aged Mom: My realistic 2020 New Year’s resolutions. Some involve doughnuts.By midafternoon, the temperature in Chicago was 100, Baltimore reached 99 and Washington hit 97, though the humidity made it feel like 107. In New York, it was 95 in Central Park and 100 at LaGuardia Airport in Queens. The National Weather Service said the mercury could reach 104 today, and Thursday could be bad, too. “This is a very dangerous heat wave,” Mayor Michael Bloomberg said. “It’s more than just uncomfortable. It can seriously threaten your life.” Boston reached 93, and in Philadelphia the temperature was 97, with a heat index of 110. Atlanta sweltered at 95. In Washington, the city’s transit agency distributed bottles of water to thousands of commuters at three rail stations with limited escalator service. “We don’t want to create a health situation,” said agency spokeswoman Lisa Farbstein. NEW YORK – Blistering heat settled over the eastern half of the nation Tuesday, sending man and beast in desperate search of relief: An air-conditioned subway car in New York City. A plunge into the Atlantic Ocean in New Jersey. And cold showers for suffering livestock in Ohio. The same heat wave that was blamed for as many as 164 deaths in California brought a fifth straight day of oppressive weather to Chicago and promised at least three days of brow-mopping temperatures in the New York metropolitan area. Residents on Chicago’s South Side were evacuated from buildings by the hundreds, one day after the power went out to 20,000 customers. Illinois officials blamed three deaths on the heat. The blistering temperatures also scorched Conyers, Ga., where a high school football player died one day after collapsing at practice. “I am pretty much dying,” said Grace Hartmann, a New York University student. “I’m from California, where it’s not this hot and not humid. To be honest, I can’t believe it’s going to be hotter” today. With a disastrous 10-day power outage in Queens still fresh in memory, New York City adopted energy conservation measures. Thermostats in city offices were set at 78, up from the usual 72, and large municipal installations such as the Rikers Island jail used backup generators. The New York skyline will reflect the cutbacks, with lights turned down on the Empire State Building and the Chrysler Building. The giant Pepsi-Cola sign on the Brooklyn waterfront was to be dimmed, as were the lights illuminating the George Washington Bridge, the Brooklyn Bridge and other spans. Utilities in New York and Pennsylvania set records Tuesday for peak electricity demand. Erin O’Brien, a spokeswoman for the agency that oversees electricity usage in six New England states, said demand today could surpass the one-day record set just two weeks ago. Demand was just shy of the record Tuesday, she said. Ohio farmers used fans and cold showers to keep their cattle cool. Even with those efforts, the animals produced about 10 pounds less milk per day because of the heat, said farmer Clark Emmons of Fayette, Ohio. Colonial Downs, a horse track in New Kent County, Va., canceled racing because of the 100-degree heat. But gamblers still could take refuge in the air-conditioned simulcasting area, where they could watch and bet on races taking place elsewhere. In New Jersey, soaring temperatures were suspected in a huge fish kill at a Piscataway lake, and beachgoers were on the sand and in the water before most people had arrived at work. Diana Tredennick of East Brunswick, N.J., slathered herself with sunscreen before 8:30 a.m. “I’ll be in the water a lot,” promised Tredennick, who brought along a cooler filled with ice and water.160Want local news?Sign up for the Localist and stay informed Something went wrong. Please try again.subscribeCongratulations! You’re all set!