Temperatures soar to triple digits as heat wave scorches millions: Live updates

'Dangerous heat', Power outages reported, Tourists grapple with heat in nation's capital, The climate change connection to heat, Humidity is adding to the misery, How long will the heat last?, Heat index forecast map, Watch for heat-related illnesses

WASHINGTON – A record-setting heat wave will continue to blast most of the eastern U.S. on Tuesday, June 24, forecasters said, with temperatures expected to soar to near 100 degrees for tens of millions of people.

This comes a day after temperatures topped 100 degrees in both Newark, New Jersey, and downtown Baltimore and thousands of customers lost power due to the excessive heat.

Extreme heat warnings and heat advisories remained in place all the way from St. Louis to Boston on June 24, the 'Dangerous heat', Power outages reported, Tourists grapple with heat in nation's capital, The climate change connection to heat, Humidity is adding to the misery, How long will the heat last?, Heat index forecast map, Watch for heat-related illnesses said. Other cities enduring these alerts include Chicago, Detroit, Cincinnati, Pittsburgh, Philadelphia, Washington D.C. and New York City.

'Dangerous heat', Power outages reported, Tourists grapple with heat in nation's capital, The climate change connection to heat, Humidity is adding to the misery, How long will the heat last?, Heat index forecast map, Watch for heat-related illnesses

Manhattan is shrouded in an afternoon haze seen from Staten Island on June 23, 2025 in New York City. Temperatures in New York City reached into the high 90s as the first heat wave of the year moved across parts of the Midwest and East Coast.

About 33 million people, almost 10% of the country, will feel blistering 100-degree heat on June 24, meteorologist Ryan Maue told the Associated Press. Maue added on X that every state along the Atlantic coast from Florida to Maine could hit 100 degrees on June 24.

'Dangerous heat'

"Dangerous heat will maximize across much of the Northeast and mid-Atlantic early this week," said AccuWeather meteorologist Jacob Hinson in an online forecast June 23.

In major cities such as Washington, D.C., Baltimore, Philadelphia and New York, the temperature was forecast to approach 100 degrees through at least June 24, which would mark the first time in many decades that triple-digit heat has been experienced in June, AccuWeather said.

Even parts of eastern and northern New England, including Boston and Portland, Maine, which are sometimes excluded from extreme heat, will come within a few degrees of 100 when the heat peaks on June 24, AccuWeather said.

Meanwhile, overnight lows are forecast to drop only into the 70s, with urban centers along the East Coast struggling to drop below 80 degrees at night, the National Weather Service said.

In fact, the temperature failed to drop below 80 degrees in New York City, Newark and Philadelphia on the morning of June 24, the weather service reported.

Power outages reported

Thousands of power outages were reported in both New Jersey and Pennsylvania on June 24. Over 4,000 people in New Jersey were without power in the midst of the extreme heat wave, according to online data. That's down from over 30,000 on June 23.

And in Pennsylvania, thousands could be without power for days after a fire damaged an electrical substation in northern Adams County, according to Met-Ed estimates.

As viewed early on June 24, estimates for the restoration of power for several thousand in the area was listed as 11 p.m. on Thursday, June 26.

– Kyle Morel and John Connolly, NorthJersey.com; Harrison Jones, Hanover Evening Sun

'Dangerous heat', Power outages reported, Tourists grapple with heat in nation's capital, The climate change connection to heat, Humidity is adding to the misery, How long will the heat last?, Heat index forecast map, Watch for heat-related illnesses

Tourists grapple with heat in nation's capital

Evidence of the near 100-degree temperatures in Washington D.C. was evident Monday afternoon on the National Mall as tourists, lined up at street vendors selling water and ice cream, took refuge in the shade of trees and camped out in museums to beat the heat.

At a small water fountain and splash pad near the Washington Monument – which was closed due to the heat – Harikrishna Gopalan and his family washed themselves off after a short, humid walk from the Smithsonian’s National Air and Space Museum.

Gopalan, 42, who is from Dubai, said he was surprised by the sweltering heat in Washington but said it’s comparable to a “winter afternoon” in his home country.

He added, however, that Dubai seems much more prepared to deal with the heat. For example he said businesses and museums shift their hours to stay open until nightfall and bus stops are equipped with air conditioners.

“I wish the museum didn't close at 5:30,” he said, tugging on the neck of his sweat-drenched shirt. Nearby, his daughter took off her shoes and splashed in the water.

“I knew it was going to be hot – but not like this,” Gopalan added.

To avoid the worst of the heat, Samantha Larsen rearranged the itinerary of her family’s trip to Washington from Louisiana.

Instead of walking along the National Mall on Tuesday, they toured the monuments around 8 p.m. on Monday, though the heat index was still near 100 degrees when they reached their first stop.

Using her hand to shield her eyes from the setting sun, Larsen said she was glad for the schedule change so she could spend Tuesday inside the nearby museums.

“We are definitely staying inside all day tomorrow,” she said, squinting as she looked up at the closed Washington Monument.

The climate change connection to heat

Of all the weather impacts linked to human-caused climate change, extreme heat poses the biggest threat to human life – more dangerous than even floods or hurricanes.

Scientists have warned that such extremes are fast becoming the new normal – while also upending assumptions about which regions might be spared the worst of climate change.

"A lot of people ask the question, 'where is it safe to be?' And the answer is probably – no place," said Howard Frumkin, an expert in environmental and occupational health sciences at the University of Washington. "We did not think the upper Midwest was going to be vulnerable to heat extremes."

The heat was also being felt in Britain, while the Arctic state of Alaska registered its first ever heat advisory last week. Last month, China saw its temperatures soar.

Humidity is adding to the misery

This will particularly be the case in the mid-Mississippi and Ohio Valleys, but also into the Great Lakes and mid-Atlantic and Northeast. "That means the heat index, or feels-like temperature, will be in the triple digits on one or more days for some cities in the Midwest and Northeast," he said.

How long will the heat last?

Extreme heat is expected to last through much of this week, the weather service said June 23. The most significant heat impacts are anticipated across the Mid-Atlantic through Thursday, June 26 and the eastern Ohio Valley into Friday, June 27, "leading to several consecutive days of oppressive heat."

The longest duration of well above-average temperatures will be centered over the eastern Ohio Valley into Friday June 27, the weather service said.

Heat index forecast map

This heat level can be dangerous to anyone without effective cooling and/or adequate hydration, especially those engaging in lengthy outdoor activities, the weather service warned. Heat-related illnesses increase significantly during extreme heat. "Take action when you see symptoms of heat exhaustion and heat stroke," the weather service said.

Staying hydrated and taking breaks away from the sun are helpful practices during the ongoing heat wave, Dr. Evan Kuhl, an emergency care physician at the University of Louisville's Jewish Hospital, said during a news conference June 23.

Certain groups are at a higher risk for heat-related illnesses, including the elderly and people with pre-existing health conditions, Kuhl said. With this in mind, it is a good idea to check on neighbors as the warm weather continues.

Contributing: Leo Bertucci, Louisville Courier Journal; Reuters