Humidity will rise with the readings, according to the agency, and the combination of moist air and high temperatures will make conditions feel even worse. New York’s five boroughs are under a heat advisory until 8 p.m. Sunday.
“There is a big Bermuda high over the ocean and it’s pumping in hot and humid air from the south and southwest,” said Gary Best, a meteorologist with Hometown Forecast Services Inc. in Nashua, New Hampshire. “I really don’t see any records with this, but it will certainly be hot enough.”
High temperatures in the large U.S. cities can affect energy markets as more people turn to air conditioners to keep cool. Natural gas will be used to fuel about 32 percent of power plants this year according to the Energy Information Administration.
From 1999 to 2009, heat killed an average of 658 people per year, according to the U.S. Centers for Disease Control and Prevention in Atlanta.
Temperatures in parts of Massachusetts, including Boston, New Hampshire, Connecticut and Rhode Island, may feel as though they have topped 100 degrees Fahrenheit (38 Celsius), according to the weather service.
“The combination of hot temperatures and high humidity will combine to create a situation in which heat illnesses are possible,” the agency said in a heat advisory. “Stay in an air-conditioned environment, stay out of the sun and check in on relatives and neighbors.”
Temperatures are expected to be about 8 degrees above normal, on average, through the next five days in the U.S. Northeast and Canadian Maritime Provinces, according to Matt Rogers, president of the Commodity Weather Group LLC.
New York City highs may reach 91 today, 93 tomorrow and 92 the next day. Boston’s high is expected to be 96 today, the weather service said. That would be the third day of readings over 90, making it a heat wave for the Massachusetts capital.
A heat wave is defined as at least three days in a row with temperatures at 90 or more, Best said. New York, as well as Philadelphia, will probably also log an official heat wave by the end of the weekend, he said.
Yesterday’s high in New York’s Central Park was 87, according to the weather service.
Best said cooler weather are expected to arrive next week, ending the streak.
“Into next week, Monday, Tuesday, Wednesday, it won’t be quite as hot,” he said.
Hot weather is forecast to persist in California’s Central Valley, according to the weather service. The high in Bakersfield may reach 106 today. It was 108 for each of the first four days of July and has been above 100 since June 27.
To contact the reporter on this story: Brian K. Sullivan in Boston at firstname.lastname@example.org
To contact the editor responsible for this story: Dan Stets at email@example.com