It’s difficult to miss the heat in Georgia.

As it turns out, that’s been the case throughout the world.

Last month was the hottest September since modern record-keeping began, researchers at NASA's Goddard Institute for Space Studies told ABC News.

It was also the 11th month of record-high temperatures in the past 12 months, with the exception being June.

That’s not the case in Atlanta. But the city still had the third-warmest September on record, tying with 1980, according to data from the National Weather Service. The warmest average local temperature in September was 83 degrees in 1925, followed by 80 in 1921.

Atlanta experienced 14 days of temperatures 90 degrees or higher in September and six record highs since late April, including one set Tuesday.

“This year, we’ve had 88 days of 90+ degree heat …,” Channel 2 Action News meteorologist Brian Monahan said. “That’s two short of the record set in 2010 and 1981 (90).”

He added that Atlanta has a small chance to reach 90 degrees Wednesday, which would break a 78-year record high of 87 for this day.

Eberhard Faust, the head of climate risks research for reinsurance company Munich Re, told ABC News a “global, long-term warming trend,” driven in part by “human-made climate change,” is one of several factors that may have influenced recent weather.

El Niño may be another factor. The climate irregularity, which can trigger disruptions in temperature, precipitation and wind, occurs when warmer-than-average sea surface temperatures persist across the equatorial Pacific Ocean for six months or longer, meteorologists said.

“Global mean temperatures are always pushed up by the warm ocean surfaces in the Pacific area,” Faust said.