As a nationwide heat wave was expected to peak in many places around the United States on Sunday, forecasters are predicting record-high daily temperatures in New York City and other parts of the Northeastern region.

New York City's previous July 24 record of 97 degrees was expected to be broken by a couple of degrees. The all-time high for Central Park was 106 degrees in 1936.

Several days of a heat wave prompted officials to prepare for high temperatures.

66 million people live in areas with dangerous levels of heat on Saturday. The heat index is a measure of how hot it is outside.

Large sections of the Midwest, including Kansas, Missouri and Oklahoma, are facing high temperatures along with areas from Southern California to the coast of North Carolina.

Parts of the Texas Panhandle and the Tennessee Valley were expected to break daily temperature records on Sunday.

He said that temperatures on Monday should be close to Sunday's, but then moderate after that in the Northeast and other areas of the country.

He said it was Tuesday by the time we got a push of cooler air into the Northeast and parts of the Mid-Atlantic.

Hypertensive cardiovascular disease and emphysema were listed as contributing factors in a heat-related death that was confirmed late Saturday. The location and time of the victim's death were not immediately released.

The peak megawatt usage on Saturday in New York City and the nearby suburban county of Westchester was about 10,300, less than this month's high of 11,500megawatt, according to Philip O'Brien, a spokesman for Con Ed. The peak was lower than in the past, with the previous record being 13,300megawatt.

He said that the decline in usage is due to the use of more energy efficient appliances. After what we've been through this week, only 27 customers were out of service late Saturday.

The system has been fortified and it is holding up according to Mr. O'Brien.

New York City officials want residents to use less energy. It was suggested to turn up the air-conditioning to 78 degrees.

The city said on social media that you can hit the beach or the pool to stay cool.

The heat emergency was declared by the mayor. The action made libraries available as cooling stations and placed air-conditioned buses throughout the city.

The Boston triathlon was postponed due to the weather in Boston. The organizers of the New York City triathlon shortened the bike portion of the race.

The heat emergency in Boston was extended through the weekend. The heat index in Boston could hit 105 degrees on Sunday.

In the United States, hundreds of people die from extreme heat each year. The National Weather Service suggests that people drink fluids, stay in cooler rooms, and keep out of the sun to stay safe.

While tying a single heat wave to climate change is difficult, heat waves around the world are growing more frequent and dangerous.

The number of hot days in the United States increased from two per year in the 1960s to six per year in the 2010s according to the National Climate Assessment.