As metro area temperatures crept toward the mid-90s on Monday, meteorologists in the region were singing what has become a common refrain — it’s hot. On Monday, metro Atlanta marked 87 days this year with temperatures above 90 degrees, according to Channel 2 Action News meteorologists.
With similar temperatures expected for the next several days, the metro area is on track to break records set in 1980 and 2011 when the area saw 90 days with temperatures above 90 degrees. The 30-year average (measured against 1981 - 2010 data) is about 44 days per year above 90 degrees, said Channel 2 meteorologist Brian Monahan.
So why is it still so hot?
“The heat is being caused by a strong high pressure area over the southeast that hasn’t broken,” Monahan said. “This is what’s driving our September heat and soon to be early October heat.”
That high pressure — air from the atmosphere that is pulled toward the ground and compressed — is keeping things dry and feeding the drought, he said. “Because the ground is so dry, that means all the sun’s energy from sunrise to sunset doesn’t have to evaporate standing water on the ground,” he said. “It goes right into heating the ground, which eventually heats the air.”
Last week, the National Weather Service issued a statement about significant short-term severe drought conditions over north and central Georgia. “The combination of late-summer heat and lack of precipitation has resulted in a sharp increase in drought intensity and coverage over north and central Georgia this week,” said weather service officials.
High daytime temperatures and a lack of rainfall quickened soil moisture loss. “This type of quickly-escalating drought impacts can often be referred to as a ‘flash drought,’ and in these situations the persistent high temperatures play more of a role than the rainfall deficits.”
The normal temperature for this time of year is a high of 78 degrees and a low of 60 degrees according to data from the National Weather Service in Peachtree City. By late afternoon Monday, the 96 degree temperature topped the previous record of 91 degrees which was set in 1941.
Recent headlines have demonstrated the perils of such high temperatures. Last June a worker died while picking tomatoes on a farm in Colquitt County. In August, a 16-year-old student at Clayton County’s Elite Scholars Academy collapsed and later died after participating in outdoor conditioning drills believed to be in violation of district policy.
Since the 1960s, heatwaves have become more frequent and longer lasting in Atlanta, a trend that can be seen throughout the entire southeast, said Kristina Dahl, Senior Climate Scientist for Union of Concerned Scientists. Over the past decade or so, there has been on average in the southeast more days above 95 degrees than there were in the 2000s or 1990s, she said.
The group, a 50-year-old nonprofit which uses science to address global problems, said the patterns are in line with climate changes. “This is consistent with what we expect to happen as we warm the globe on average. We expect more days of extreme heat. When we look to the future, we see places like Atlanta and all across the country experience more frequent and more intense heat as our carbon emissions continue to rise,” said Dahl referencing “Killer Heat in the United States,” the July report from the group which looked at the impact of deadly heat in the U.S. and ways to avoid a worst case scenario.
“There is always going to be year-to-year variability in how many days above 90 Atlanta has or any place has,” Dahl said. “It is important to keep that in mind because next year could be cooler or the year after that it could be hotter.”
For now, a change is on the horizon.
Later this week the high pressure area will weaken and allow cooler air to move in, though there will be little to no rain through the work week or over the weekend, just an isolated shower or storm chance, Monahan said. Cooler, wetter weather is expected next week.
Support real journalism. Support local journalism. Subscribe to The Atlanta Journal-Constitution today. See offers.
Your subscription to the Atlanta Journal-Constitution funds in-depth reporting and investigations that keep you informed. Thank you for supporting real journalism.