Forsyth County smells bad. It smells like sewage. No, it smells like rotten eggs. It smells in North Forsyth. Or, wait, it smells in South Forsyth, too. And near the Cherokee County line. OK, basically everywhere.

“We’ve been looking at it for over a week,” said Chris Grimes, director of Forsyth County’s emergency management department, “trying to figure out what’s going on.”

Since last Wednesday, residents have flooded officials with Forsyth County government and the city of Cumming with complaints about strong, persistent foul odors permeating all parts of the community.

Grimes says the city and county have “spent a lot of hours” looking for the source. They’ve inspected sewers, water treatment plants and creeks. They’ve talked to Tyson Foods about its poultry rendering plant on Leland Drive in North Forsyth, and the Tyson and Koch Foods chicken processing plants in downtown Cumming, all common sources of odor complaints over the years.

Tyson told the Forsyth County News that it has received some complaints about an odor near its rendering plant and investigated its equipment and facilities. A formal complaint was filed with the Georgia Environmental Protection Division on Aug. 17, according to its Complaint Tracking System, and was forwarded to the Georgia Department of Agriculture.

Tyson said it has communicated with both agencies, as well as the county, in the last week about the complaints.

“If Tyson becomes aware of any issues with our operations, we work to promptly address and resolve them,” said Morgan Watchous, communications manager with Tyson.

Even more confusing, complaints from residents described different types of smells in different parts of the county, Grimes said.

“There was not one specific source for the smell that we could come up with so far,” Grimes said.

Without an obvious cause of the smell, Grimes called the National Weather Service. He asked them to look into the weather patterns around Forsyth County.

The National Weather Service said that conditions in the area had been “muggy” with “stagnant air – not a lot of airflow,” Grimes said.

“Those smells are just not moving like they normally would,” he added.

According to Bill Murphey, state climatologist and chief meteorologist for the Environmental Protection Division of the Georgia Department of Natural Resources, the state has experienced a lot of humidity this summer, mostly due to a “southwesterly flow” that brings moisture from the Gulf of Mexico.

That increases the amount of water vapor in the air, he said, which can “play a role in maybe holding odors around longer,” Murphey said.

It’s also possible that Forsyth County has been experiencing a meteorological condition known as a temperature inversion.

Normally, temperature decreases with height in the lower atmosphere, Murphey said, and air is free to rise. But sometimes a layer of warm air can develop above the surface during high-pressure systems when the weather is fair and calm, trapping colder air beneath it.

That layer “acts as a lid on the atmosphere,” Murphey said, and blocks air – including the odors in it.

“Odors can build up under those meteorological conditions,” he said.

Temperature inversion can be impacted by several things, Murphey said, from the sun, atmospheric conditions, even geography. In fact, it is most common in rural areas (like, say, North Forsyth) and valleys (like around Sawnee Mountain).

So it’s possible that a perfect storm of factors have combined to amplify the smelliest parts of Forsyth County.

Murphey said it would take “a Ph.D. study” to know for certain.

“At this point, it’s a theory,” Grimes said.

Which means Forsyth County’s collective nose could be at the whim of Mother Nature.

But there is hope. All it takes is a new weather pattern to come along and “push” or “break” the temperature inversion, Murphey said. In short: it takes wind.

Friday already saw signs of change.

After days of “calm” winds, according to the National Weather Service, Forsyth County experienced a stronger flow from the southwest, with top speeds of 10 MPH. The forecast for Saturday calls for even stronger gusts of up to 25 MPH as the remnants of Hurricane Laura move into the region.

“There should be fairly decent (air) mixing as that system approaches us,” Murphey said.