More than 90 million people across the country are under various heat warnings for dangerously high temperatures. Sunday is expected to bring warmer temperatures to the Northeast.
In New York City, at least one person died of heat exposure on Saturday, a spokeswoman for the city’s medical examiner’s office said. The man also had other medical problems, the spokesman said. The city will record a high of 97 degrees on Saturday.
Among other heat-related deaths during this week’s heat wave was a 73-year-old man who was found dead in a room without air conditioning in Allentown, Pennsylvania, on Thursday, the medical examiner said. He had several underlying medical conditions, including diabetes.
In Dallas, a 66-year-old Dallas woman also died last week of complications, county officials said. On Wednesday, a 22-year-old hiker died of dehydration and exposure after running out of water in a South Dakota national park, officials said.
Cities including Philadelphia, Boston and Washington, D.C., will see temperatures in the 90s, with humidity intensifying and could feel into the triple-digits.
The extreme conditions — which experts say are becoming more common around the world due to climate change — have led local authorities to declare heat emergencies to free up resources to deal with the heat millions of people are enduring. Officials are asking people to stay hydrated when spending time outdoors and to exercise caution when visiting vulnerable communities and neighbors.
“A wide range of high temperature records are forecast to be tied or broken from the Mid-Atlantic to New England (Sunday), with many locations in the upper 90s and heat indices expected to eclipse 100 degrees,” the forecast center wrote.
Metro areas will experience a heat rush on Sunday as the temperature rises
Boston has been under a heat emergency warning since Tuesday, and with continued high heat in the forecast, Mayor Michael Wu extended it until Monday. By Sunday afternoon, the city’s temperature had reached 100 degrees, the highest for a calendar day in 89 years.
City dwellers have opened cooling centers, splash pads, indoor pools and public library spaces for relief from the heat.
A scorching heat wave knocked out power to about 7,500 customers in Boston’s Dorchester neighborhood on Sunday, power company Eversource said in a statement to CNN. The company was able to restore power to about 12,500 customers earlier Sunday, they said.
In New York City, where a heat advisory remained in effect until 8 p.m. Sunday, Con Edison workers restored “scattered outages caused by scorching heat,” the power provider said. The company’s website showed about three dozen customers without power as of Sunday afternoon.
In Philadelphia, where Sunday’s high is expected to reach 99 degrees, officials have extended a heat health emergency. Cooling centers, special group home visits and enhanced day trips for people experiencing homelessness are available on weekends.
To the west, in Greensburg, Pennsylvania, near Pittsburgh, more than 10,000 customers were without power Sunday after storms a day earlier.
“With another round of storms in the forecast later today, delays and additional outages are possible,” West Penn Power said. “As above normal temperatures also affect our service area today, customers should take the necessary steps to stay safe and escape the heat.”
New York Governor Kathy Hochul urged people in her state to take advantage of cooling centers and check on especially vulnerable communities.
“Everyone should be vigilant this weekend, watch for any signs of heat-related illness and take care of each other,” Hochul said in a news release.
Extreme heat is the leading cause of weather-related deaths in the United States
In fact, according to data tracked by the National Weather Service, heat deaths have outnumbered hurricane deaths 15-to-1 over the past decade.
Part of the problem is that high humidity makes it feel like it’s over 100 degrees in many areas, and makes it harder for the body to cool down.
Maricopa County, Arizona, has had 29 confirmed heat-related deaths since March, according to the county Department of Public Health. During the same period last year, 16 people died due to heat, according to the health department. Meanwhile, dozens of other heat-related deaths in the county remain under investigation.
New York City sees an average of 10 heat stress deaths each year, according to a report commissioned by the city’s health department last year. A lack of home air conditioning “continues to be an important risk factor for heat stress death,” the report found.
It is not known whether the person who died in the heat on Saturday had air conditioning.
CNN’s Isa Kaufman Geballe, Haley Brink, Allison Chinchar Rachel Ramirez, Liam Reilly Benjamin Schiller and Emily Chang contributed to this report.

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