Summer in Georgia is the season for peaches and watermelons. But, while you can get them fresh from the farm, you yourself might not be as fresh as they are.
If you’ve ever been to the Peach State during summertime, you know the feeling of the hot and thick humid air that hugs you tightly. In Atlanta, and across Georgia, it’s not just about adjusting to the heat. Humidity is really what makes everything feel so hot, sticky and muggy.
With temperatures averaging 80 degrees F (26 C) to 95 degrees F (35 C), Georgia summer is the hottest and most humid time of the year in the state.
How Humid Does Georgia Get in the Summer?
To determine how muggy Georgia summers can get, let’s take a look at its relative humidity. Relative humidity measures water vapor relative to the temperature in the air or the actual amount of water vapor in the air compared to the total amount of vapor that can exist in the air at its current temperature. It is usually expressed as a percent.
Relative Humidity = (Actual Moisture / Maximum potential moisture at current temperature) ✕ 100
In the Empire State of the South, the hourly relative humidity throughout the year averages from 60% to 75%. In the summer, this can go as high as 98%, depending on where you are in the state.
Atlanta and the Piedmont
In the Piedmont and the rest of North Georgia, humidity typically follows a steady climb. It usually starts at about 70% average humidity in June and reaches an average of 75% by August.
In Atlanta, relative humidity can go as high as 86%, typically around July 25. This is considered to be the city’s “muggiest day.” The air is most saturated (around 82% relative humidity) at 7 a.m., but as the temperature climbs, it starts to “dry out” to about 52% relative humidity by 4 p.m.
Savannah and the Coast
If you’re in Georgia in the summer and want to experience a tropical environment, head to Savannah. It basically has tropical vibes and weather to boot at this time. With its location right on the Atlantic Ocean and the fact that the city is surrounded by wetlands, humidity here rarely diminishes. It peaks in August, which has an average humidity hitting 79-80%.
Moreover, quick but intense afternoon thunderstorms just leave the air in Atlanta even steamier than before. This is like a routine here and provides a brief cool down that will inevitably result in a steam bath immediately afterward.
Summer in Savannah and the rest of the Coast is obviously not all about high temperatures or dry heat. As August is also within the Atlantic hurricane season, these afternoon showers are to be expected. Even if no major storm hits the city directly, outer bands and tropical depressions frequently pour tons of rain on the coast.
In fact, summer is when Savannah receives much of its rainfall in the year. By June, the amount of rain the city receives more or less doubles at 4.1 inches, peaking in August with 5.3 inches, and continuing well until September at 4.3 inches. Bottom line: Summer is Savannah’s wettest season, so high humidity can’t be helped.
Central Georgia
In Central Georgia, cities like Macon and Augusta often see the highest actual temperatures in the state. For instance, Augusta’s muggy season lasts about four months. During the summer, the chance of having a muggy day rises from 47% to 76% over the course of the season. It peaks in late July when oppressive conditions are present 91% of the time.
Meanwhile, in Macon, the muggy season lasts for 3.7 months (roughly from the end of May to mid-September), with July having the most number of muggy days. July 22 (or thereabout) typically has the highest humidity at 61%.
South Georgia
As you get nearer to the Florida border, you’ll also feel the humidity get more intense. For instance, in Valdosta, the chance of a day being muggy reaches a staggering 98% in early August.
Summary: Relative Humidity in Georgia
| City | Region | Relative Humidity | Peak Month |
| Atlanta | North Georgia | Average: 70-75% Peak: 86% | July |
| Savannah | The Coast | 79-80% | August |
| Augusta | Central Georgia | Average: 47% to 76% Peak: 91% | July |
| Macon | Central Georgia | Ranges from 40%-50% Peak: 61% | July |
| Valdosta | South Georgia | 98% | August |
Why is Georgia So Humid in the Summer?
Summer in the Peach State is so humid thanks to two main factors.
Bermuda High
The Bermuda High is a high-pressure system located over the Atlantic Ocean. Its clockwise circulation directs the path of tropical systems and determines where they make landfall. However, it’s not always certain how the Bermuda High may affect a system. It’s highly unpredictable.
“There are many factors that can impact the strength, orientation and location of the high,” explained AccuWeather veteran meteorologist Dan Kottlowski, who’s been studying and forecasting tropical weather for more than 40 years. “It’s almost like a cork in a bathtub. Strong upper-level systems can force the high to move either west or east and north to south, and environmental conditions under the high like sea-surface temperatures can cause the high to weaken more than expected.”
In the early part of the hurricane season, the Bermuda High tends to be stronger. As a result, it moves westward into the northern Gulf of Mexico. Combined with the intense summer sun, all this moisture gets trapped near the ground and creates the sauna effect those living or frequently in Georgia during summertime know so well.
Corn Sweat
Another big reason for Georgia’s high summer humidity is corn sweat. Yes, you can think of it as the corn fields sweating under the scorching sun—in a way. Corn sweat is a natural process (technically called evapotranspiration) where plants draw water from the soil, take what it needs, and then release the rest into the atmosphere (evaporation).
Just like people, the hotter it is, the more the corn needs water and the greater amounts of water that it evaporates. According to the U.S. Geological Survey, an acre of corn can release 3,000 to 4,000 gallons of moisture in a day.
“Any place you have corn fields and it’s hot, you get corn sweat,” AccuWeather meteorologist Dale Mohler told National Geographic. “It can bump the humidity on a hot day by up to 30 to 40 percent.”
With corn sweat adding moisture to the atmosphere, the result is an even hotter and more unpleasant summer time.
