Multiday warnings of extreme heat landed in New York, Boston and Philadelphia on Wednesday as sultry weather pushed east just ahead of Fourth of July celebrations in a region that revels in its role as a historic hub of U.S. independence.
Temperatures in the high 90s Fahrenheit (30 degrees Celsius) were forecast for the Northeast; Philadelphia and Boston could top 100 by Thursday. Throw in humidity, and the real-feel heat index will be even higher at times, the National 蜜桃视频app Service said.
A 鈥� high-pressure systems above a region that trap heat and humidity 鈥� has been , from the Midwest to the East Coast. It will add much discomfort amid 250th birthday parades, ship flotillas, outdoor concerts and, in Boston, a public reading of the Declaration of Independence from a historic balcony Saturday.
New York Mayor Zohran Mamdani advised residents to stay cool inside and avoid 鈥渆xtraordinary temperatures.鈥�
鈥淭o be breaking into triple digits over the course of these many next days 鈥� it is of immense concern given that too often the heat is something that is underestimated,鈥� Mamdani said.
Concrete and steel aggravate hot weather
Humidity is not uncommon in the Northeast. But Dr. Alexander Azan of NYU Langone Health in New York said high air temperatures and humidity are a dangerous combination.
鈥淭heir body doesn鈥檛 have that level of acclimatization to respond appropriately to the heat, and so heat stress in the form of what we call heat exhaustion, and in more severe cases, heat stroke, can occur at much lower temperatures than we see in people who live in the South,鈥� Azan said.
Cities in particular are at greater risk, experts say.
“The concentration of concrete, asphalt, steel, all of those materials help to retain heat,鈥� said Vijay Limaye, a climate scientist at the Natural Resources Defense Council. 鈥淭he number on your phone may actually not reflect the true temperature profile that you鈥檙e going out into.鈥�
New York City said more than 200 teams of government workers and volunteers will check on homeless people and encourage them to get inside. There will be hundreds of cooling centers, from the Javits Center convention hall to vans to outdoor spots with misting fans.
Relief for kids 鈥� and pets
The American Kennel Club鈥檚 Museum of the Dog in New York is allowing visitors to bring their dogs to cool off, through Sunday. Executive Director Christopher Bromson said he got the idea from seeing his own Newfoundland sprawled on the museum鈥檚 cool floor.
鈥淚 thought every dog should have access to this,鈥� he said.
In Washington, D.C. where the high temperature was 95 F (35 C), thirsty children reached for cold bottles of water from U.S. Park Police as they waited in line for the Ferris wheel on the National Mall.
In the Midwest, meanwhile, heat risks remained. Taylor Harnist, whose Cincinnati business installs and repairs air conditioners, said he was trying to keep his employees comfortable with breaks, water and electrolyte drinks.
鈥淵ou get an attic job when it鈥檚 this hot, we do them but it鈥檚 strenuous,鈥� Harnist said. 鈥淚t鈥檚 so hot the attics will reach temperatures of 145 degrees.鈥�
Jeff Schlegelmilch, associate professor at Columbia University Climate School, said heat is one of the easiest things to attribute to climate change.
鈥淲e have seen a continued increase in longer summers, hotter temperatures, hotter temperatures earlier on, more evaporation of moisture, higher humidity 鈥� effects like that,鈥� he said.
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Associated Press writers Jennifer Peltz in New York and Scott Bauer in Madison, Wisconsin, contributed to this report.
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