A dangerous heat dome is bringing record temperatures to millions this weekend.
Millions of Americans are gearing up to celebrate the country’s 250th birthday under dangerously hot skies, as a sprawling heat dome grips much of the East Coast just in time for the Fourth of July weekend.
The National Weather Service has warned that temperatures could stay at or above 100 degrees for several days, with the heat index, how hot it actually feels, climbing as high as 115 degrees in cities including Washington, D.C., Philadelphia and New York.
Just how hot it’s getting
By Thursday morning, temperatures were already nearing 90 degrees in Washington and New York. Later that day, Central Park hit 100 degrees and felt like 106 with humidity factored in, the hottest it has been there in 15 years. Washington, meanwhile, is on track for four consecutive days at or above 100 degrees, something that has only happened twice before in the city’s history.
Forecasters say the heat is being driven by a stubborn area of high pressure parked over the central and eastern United States, a pattern known as a heat dome. Dry soil from an ongoing drought across the coastal Northeast is making things worse, since there is little moisture left to absorb the sun’s energy before it bakes the ground instead.
Celebrations go on despite the heat
The extreme conditions are complicating plans for a series of high-profile events. President Donald Trump is set to host an outdoor celebration Saturday marking the nation’s 250th birthday, and he has indicated he intends to speak outside regardless of the forecast, joking that he would deliver a lengthy speech even in extreme heat just to prove he could. Capitol Police have already limited attendance at a rehearsal for a related July 4 concert in Washington to essential personnel only, citing safety concerns for large outdoor crowds.
In New York, Mayor Zohran Mamdani urged residents to stay indoors and stay cool, adding that even today’s high-profile wedding between Taylor Swift and Travis Kelce at Madison Square Garden would be an indoor affair, calling it a smart example for the rest of the city to follow.
The heat stretches far beyond the East Coast
The dangerous conditions are not confined to the East Coast. Canada is also seeing unusually high temperatures this week, with highs nearing 99 degrees in Ontario and heat warnings posted across Quebec, including Montreal and Quebec City.
Closer to home, the picture varies region by region heading into the holiday. First, in southeast Michigan, hot conditions are expected to break this evening as storms move through, with forecasters warning of a slight risk of strong to severe weather, including heavy rain, gusty winds and large hail, in the state’s southern counties, while the Upper Peninsula should stay mostly dry and cooler after its own rough week of severe weather. Second, in South Florida, forecasters expect scattered storms through the holiday weekend with highs hovering around 90 degrees each day.
A pattern scientists say is here to stay
Relief is on the way for parts of the Northeast, where temperatures are expected to dip slightly on the Fourth alongside a chance of severe thunderstorms, with a more noticeable cooldown arriving by the weekend as cooler air moves in from the north. Still, scientists note that heatwaves like this one have grown more frequent, more intense and longer-lasting because of human-driven climate change, with global temperatures already up roughly 2 degrees Fahrenheit since the industrial era began.