New York (AP) – Unprecedented and near-historic weather patterns are affecting much of the United States this week due to a Dangerous Heat Dome. Some areas are experiencing triple-digit temperatures not felt in over a decade.
Heat waves pose significant risks as cities like Boston, New York, and Philadelphia face extreme conditions early this summer. High-pressure systems settled over the eastern United States trap heat from the southwest.
Key metrics of high-pressure intensity set records on Monday. It recorded the third-highest reading for this date, contributing to a “historic nearby” heatwave, according to Ryan Maue, a former Director at the National Oceanic and Atmospheric Administration (NOAA). Forecasters predict the worst of the heat will hit northeastern cities on Tuesday.
“It’s going to feel hot, almost like an air fryer,” Maue remarked. “This is a three-day dangerous heatwave testing the limits of city dwellers, especially the most vulnerable to extreme heat.”
Thermal domes form when extensive high-pressure areas in the upper atmosphere act as a barrier, trapping heat and moisture. A heat wave typically consists of unusually high temperatures sustained for more than three consecutive days.
Where Heat is Most Severe
On Monday, nearly three-quarters of the U.S. population (245 million people) sweltered in temperatures exceeding 90 degrees Fahrenheit (approximately 32 degrees Celsius). By Tuesday, nearly 10% of the country could experience temperatures at 100 degrees (about 38 degrees Celsius), Maue stated. The government’s Heat Health Website indicated high levels of heat risk in areas spanning from Chicago to Pittsburgh, North Carolina, and New York.
Triple-digit temperatures are expected in unusual places, exacerbated by humidity, which makes conditions feel even more uncomfortable. New York hasn’t registered 100 degrees since 2011, while Philadelphia anticipates consecutive triple-digit days, a milestone not reached since 2012, according to Bernadette Woods, Chief Meteorologist at Climate Central.
By early Monday afternoon in downtown Baltimore, temperatures climbed into the 90s, leading to dozens of individuals cooling off at the St. Vincent De Paul resource center. The historic Broadway Market Food Hall nearby closed early due to a malfunctioning air conditioning system.
The extreme heat also led to event cancellations in West Baltimore, as reported by Eric Davis Sr. “You can’t get a heat stroke from your kids,” he mentioned. “It’s too hot today.”
NOAA meteorologist David Ross pointed out that adjusting to summer’s heat takes time, and this heat dome could be jarring for many. “Some regions may see temperature increases of up to 40 degrees compared to last week, which is significant,” he added.
Climate Change and Soil Warming
A child covers his face as water streams down at a waterfront park in Louisville, Kentucky on Sunday, June 22, 2025 (AP Photo/John Cherry)
Heat is part of the long-term global warming trend. Summers in the U.S. are now 2.4 degrees Fahrenheit (1.3 degrees Celsius) warmer than they were 50 years ago, as noted by NOAA data. Human-inflicted climate change has amplified the likelihood of this heat wave, a scenario that would have been less probable without the burning of fossil fuels. Climate Central, a non-profit organization focused on climate science, employs computer simulations to compare current weather with a hypothetical world devoid of industrial greenhouse gas emissions.
A critical concern is the extent to which humidity affects discomfort and heat-related dangers.
Maue anticipates drier air conditions. However, this might be more favorable than NOAA’s predictions. In contrast, other meteorologists warn that humidity levels could rise, making the situation stickier and potentially more hazardous.
“The key issue is the humidity from damp late spring conditions,” remarked Professor Jason Furtado, an expert in meteorology at the University of Oklahoma. “High-pressure systems can lead to significant evaporation from wet ground, which substantially raises the heat index.”
Woods foresees dew points reaching the ’70s, signaling tropical conditions, with some areas approaching the 80-degree dew point. This level feels akin to being submerged in a swimming pool, with the atmosphere feeling as if it’s enveloping you.
If such heat occurred later in the summer, the human body could adjust to the warmer seasonal temperatures. However, Woods noted the unusual timing of this heat event, which follows a relatively cool period, could surprise many. “That could be overwhelming for the system,” she concluded.
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Contributions to this report were made by Isabella O’Malley of Philadelphia and Lee Skane of Baltimore through the Associated Press.
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Source: apnews.com