More than 70 million Americans are sweating on record for the first two months of the summer because of the first two months of the summer, because climate change has noticeably rang the humidity of the Eastern States in recent decades, according to a corresponding press data analysis.
And that meant uncomfortably warm and potentially dangerous nights in many cities in recent weeks, said the National Weather Service.
Parts of 27 states and Washington, DC, had a record amount that meteorologists call uncomfortable – with average daily dew points of 65 degrees Fahrenheit or higher – in June and July, derived from the Copernicus Climate Service.
And that’s just the daily average. In a large part of the east, the overbellness continued to rise for a few moist hours to almost tropical level. Philadelphia had 29 days, Washington had 27 days and Baltimore had 24 days where the highest DEW point was simmering to at least 75 degrees, which even calls the Weater Service Office in Tampa, according to WeerService data.
Dauwpunt is a measure of moisture in the air that is expressed in degrees that many meteorologists call the most accurate way to describe the humidity. The summer of 2025 has so far had dew points that are on average at least 6 degrees higher than the Normals of 1951-2020 in Washington, Baltimore, Pittsburgh, Richmond, Columbus and St. Louis, show the AP calculations. The average humidity of June and July for the entire country east of the Rockies rose to more than 66 degrees, higher than every year since the measurements started in 1950.
“This has been a very sultry summer. The moist heat has been far up,” said Bernadette Woods Placky, main meteorologist at Climate Central.
Twice this summer climate scientist and humid expert Cameron Lee from Kent State University Measured Dauwpunt of approximately 82 degrees in his home weather station in Ohio. That is outside the various graphs that the weather service uses to describe how dew points feel.
“There are parts of the United States that not only experience greater average humidity, especially in the spring and summer, but also more extreme humid days,” Lee said. He said that super sticky days now extend in more days and more land.
High humidity does not let the air cool down at night as usually, and the stick has contributed to several nocturnal temperature records from the Ohio Valley via the Central Atlantic Ocean and up and down coastal states, said Zack Taylor, forecast operations Chief in the weather Prediction Center of the National Wather Service. Raleigh, Charlotte, Nashville, Virginia Beach, va. And Wilmington, NC, all achieved records for the hottest teasing the night. New York City, Columbus, Atlanta, Richmond, Knoxville, Tennessee and Concord, New Hampshire came close, he said.
“What really influences the body is that night temperature,” Taylor said. “So if there is no cooling at night or if there is a lack of cooling, your body cannot cool down and recover from what was probably a really hot afternoon. And so if you start seeing that for several days, it can really wear the body, especially if you don’t have access to cooling centers or air conditioning.”
An extra warm and rainy summer weather pattern is combined with climate change by burning coal, oil and natural gas, said Woods Placky.
The area east of the Rockies has been achieved on average about 2.5 degrees in the Zomerdauwpunt since 1950, according to the AP analysis of Copernicus data. In the 1950s, 1960, 1970, 1980 and part of the 1990s, the eastern half of the country had an average dew point in the low 60s, which the weather service noticeable but OK. In four of the last six years, that number was close by and even on the uncomfortable line of 65.
“It’s huge,” Lee said about the 75-year-old trend. “This shows a huge increase for a relatively short period.”
That apparently small increase in the average dew points really means the worst ultra-flexible days that used to happen once a year, now that happened several times a summer, which affects people, Lee said.
Higher humidity and heat feed on each other. A basic law of physics is that the atmosphere contains an extra 4% more water for every degree Fahrenheit (7% for every degree Celsius) warmer it gets, meteorologists said.
During most of the summer, the midwest and the east were stuck under incredibly hot high -pressure systems, which raised the temperatures, or getting heavy and persistent rain in quantities much higher than average, Taylor said. What was missing was the incidental cool front that pushes the most oppressive heat and humidity out. That eventually came in August and brought relief, he said.
Humidity varies per region. The West is much drier. The south gets more dew points of 65 degrees in the summer than the north. But that changes.
University of Georgia Meteorology Professor Marshall Shepherd said that uncomfortable humidity continues to the north, to places where people are less used to it.
Summer now said, “Are you not the summers of your grandparents.”
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Korenstein reported Van Washington and Wildeman reported from Hartford, Connecticut.
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