Why humidity makes Atlanta’s heat feel even hotter

Atlanta is no stranger to summer heat, but this week’s extreme humidity is expected to make temperatures in the upper 90s feel well above 100 degrees.

Early Monday, the National Weather Service at Peachtree City issued a heat advisory, cautioning that an oppressive combination of heat and humidity will cause afternoon skin temperatures to soar to 105-110 degrees in metro Atlanta.

These conditions are expected to last through the July Fourth holiday weekend, Christopher Rangel — a meteorologist with the National Weather Service in Peachtree City — told The Atlanta Journal-Constitution.

This is the first time in 2026 that the metro area has experienced a major heat event, and it won’t be the last, said Lindsay Marlow, the Weather Service’s lead meteorologist in Peachtree City.

“It definitely will be one to keep an eye on as we head toward the July 4 holiday weekend” and greet thousands flocking to Atlanta as one of the host cities of the 2026 World Cup, Marlow said.

“Obviously, it will be impactful for sensitive populations.”

The Centers for Disease Control and Prevention and the Weather Service are cautioning people to be careful. While anyone can suffer from heat-related illnesses at any time, they warn that adults 65 and older, people with asthma, especially children, people with heart disease, pregnant women and people working or exercising in the heat are at greatest risk.

To stay safe, experts are urging metro Atlantans to drink plenty of fluids, stay in an air-conditioned room, limit time in direct sunlight and check on older relatives, neighbors and others who may be vulnerable.

Why does the South feel so humid?

Heat alone doesn’t tell the whole story. According to the NWS, humidity makes it harder for your body to cool itself because sweat can’t evaporate as easily. If the perspiration cannot evaporate, the body cannot regulate its temperature. As a result, your body retains more heat, increasing the risk of dehydration, heat exhaustion and heatstroke.

That combination of heat and humidity is become a growing concern, explained Brian Stone Jr., director of Georgia Tech’s Urban Climate Lab and a professor in the university’s School of City & Regional Planning.

Recent research shows many cities, including Atlanta, are approaching an absolute threshold of heat and humidity that could cause a young, healthy adult’s core body temperature to rise to dangerous levels after as little as one hour spent in extreme outdoor heat, Stone said.

These cities need to take the threat seriously, he encouraged.

“Once this threshold is reached, essential activities, such as outdoor construction or garbage collection, cannot be safely performed.”

Atlanta and much of the Southeast experience a higher baseline humidity than other regions because of their proximity to the Gulf of Mexico. Regional weather patterns transport moisture from the Gulf across the region, increasing humidity, Stone explained.