The June Heat Dome Is Shattering Temperature Records

Current conditions: Tropical Storm Andrea has become the first named Atlantic storm of 2025 • Hundreds of thousands are fleeing their homes in southwest China as heavy rains cause rivers to overflow • It’s hot and humid in New York’s Long Island City neighborhood, where last night New York City mayoral candidate Zohran Mamdani delivered his victory speech after defeating former governor and longtime party power broker Andrew Cuomo in the race’s Democratic primary.

THE TOP FIVE

1. June heat wave smashes temperature records

The brutal heat dome baking the eastern half of the United States continues today. Cooler weather is in the forecast for tomorrow, but this heat wave has broken a slew of temperature records across multiple states this week:

• New York’s John F. Kennedy Airport recorded 102 degrees Fahrenheit, its hottest temperature since 1948.
• Boston also hit 102 degrees, marking the city’s warmest June day ever.
• Providence, Rhode Island, broke a monthly temperature record set in 1945.
• The mercury hit 100 degrees in Philadelphia for the first time since 2012.
• In Toronto, Canada, temperatures reached almost 97 degrees, the highest in a decade.

In Washington, D.C., rail temperatures reached a blistering 135 degrees, forcing the city’s Metro to slow down train service. Meanwhile, in New Jersey, the heat sickened more than 150 people attending a high school graduation ceremony. As power demand surged, the Department of Energy issued an energy emergency in the Southeast to “help mitigate the risk of blackouts.”

As Heatmap’s Matthew Zeitlin pointed out on Tuesday, in terms of what is on the grid and what is demanded of it, this may be the easiest summer for a long time. “Demands on the grid are growing at the same time the resources powering it are changing,” Zeitlin writes. “Electricity load growth is forecast to grow several percent a year through at least the end of the decade. At the same time, aging plants reliant on oil, gas, and coal are being retired (although planned retirements are slowing down), while new resources, largely solar and batteries, are often stuck in long interconnection queues — and, when they do come online, offer unique challenges to grid operators when demand is high.”

2. Democratic states sue Trump administration over grant cuts

A group of 21 Democrat-led states including New Jersey, Massachusetts, New York, Arizona, and California, is suing the Trump administration for cutting billions of dollars in federal funding, including grants related to climate change initiatives. The lawsuit says federal agencies have been “unlawfully invoking a single subclause” to cancel grants that the administration deems no longer align with its priorities. The clause in question states that federal agencies can terminate grants “pursuant to the terms and conditions of the federal award, including, to the extent authorized by law, if an award no longer effectuates the program goals or agency priorities.” The states accuse the administration of leaning on this clause for “virtually unfettered authority to withhold federal funding any time they no longer wish to support the programs for which Congress has appropriated funding.”

The rollback has gutted projects across states and nonprofits that support diversity, equity, and inclusion, as well as climate change preparation programs and research. The states say the clause is being used unlawfully, and hope a judge agrees. “These cuts are simply illegal,” said New York Attorney General Letitia James. “Congress has the power of the purse, and the president cannot cut billions of dollars of essential resources simply because he doesn’t like the programs being funded.”

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3. Developing nations push for more climate adaptation financing at Bonn conference

A brief update from the Bonn Climate Change Conference in Germany: A group of 44 “Least Developed Countries” have called for rich countries to triple the financing goal for climate change adaptation by 2030 compared to 2022 levels. The current target sits at $40 billion a year by 2025, a number set back in 2021 at COP26. According to Climate Home News, tripling the financing goal on 2022 levels would bring in a little less than $100 billion annually. That’s far short of the $160 billion to $340 billion that the United Nations estimates will be needed by 2030. The Indian Express also reports that developing countries have “managed to force a reopening of discussions on the obligations of developed nations to ‘provide’ finance, and not just make efforts towards ‘mobilising’ financial resources, for climate action.” The issue will also be discussed at COP30 in Brazil later this year. The Bonn conference has been running since June 16 and ends tomorrow.

4. UK aviation emissions surpass power sector emissions

In the UK, aviation is now a bigger source of greenhouse gas emissions than the power sector, according to a new report from the Climate Change Committee. The independent climate advisors say that demand for leisure travel is boosting demand for international flights, and “continued emissions growth in this sector could put future targets at risk.” Meanwhile, the UK power sector has been rapidly decarbonizing, and is now the sixth largest source of emissions. (In the U.S., electricity production is the second-largest source of emissions, behind transportation.) The report also found that heat pump installations increased by 56% in 2024, and that nearly 20% of new vehicles sold were electric. UK emissions were down 50% last year compared to 1990.

The committee applauded the progress but urged more action from the government to cut electricity prices to help speed up the transition to clean technologies. “Our country is among a leading group of economies demonstrating a commitment to decarbonise society,” said Piers Forster, interim chair of the committee. “This is to be celebrated: delivering deep emissions reduction is the only way to slow global warming.”

5. Half of North Carolina voters want to keep the IRA, poll finds

Voters in North Carolina want Congress to leave the Inflation Reduction Act well enough alone, a new poll from Data for Progress finds. The survey, which asked North Carolina voters specifically about the clean energy and climate provisions in the bill, presented respondents with a choice between two statements: “The IRA should be repealed by Congress” and “The IRA should be kept in place by Congress.” (“Don’t know” was also an option.) The responses from voters broke down predictably along party lines, with 71% of Democrats preferring to keep the IRA in place compared to just 31% of Republicans, with half of independent voters in favor of keeping the climate law. Overall, half of North Carolina voters surveyed wanted the IRA to stick around, compared to 37% who’d rather see it go — a significant spread for a state that, prior to the passage of the climate law, was home to little in the way of clean energy development.

North Carolina now has a lot to lose with the potential repeal of the Inflation Reduction Act, as Heatmap’s Emily Pontecorvo has pointed out. The IRA brought more than 17,000 jobs to the state, along with $20 billion in investment spread out over 34 clean energy projects. Electric vehicle and charging manufacturers in particular have flocked to the state, with Toyota investing $13.9 billion in its Liberty EV battery manufacturing facility, which opened this past April.

THE KICKER

As a fragile ceasefire between Israel and Iran takes hold, oil prices are now lower than they were before the conflict began on June 13.