We’re nearly a month into fall, but it’s just now starting to feel like it.

Metro Atlanta temperatures have been in the 70s and 80s since fall started Sept. 22. We even saw a few 90-degree days at the beginning of the season.

But this week, cool, dry air started setting in across the eastern half of the country. Temps dropped into the mid-30s across North Georgia in the early hours of Thursday morning. High temps have stayed in the 50s and 60s. That’s well below the average 74-degree high and 55-degree low for this time of year.

“It is going to be quite chilly ... the coolest air that we have seen in about six months,” Channel 2 Action News meteorologist Ashley Kramlich said.

It’ll be so cold, in fact, that a frost advisory is in effect for metro Atlanta through 9 a.m. Thursday, and a freeze warning is in place in far northeast Georgia until 10 a.m.

Freeze warnings are issued in the spring and fall when plunging temps could damage plants. In the fall, the first widespread freeze marks the end of the growing season. If temps are forecast to fall lower than 36 degrees but don’t quite reach the freezing mark, a frost advisory is issued.

This cool, crisp air originates from the Beaufort Sea, just north of Canada and east of Alaska, according to the National Weather Service. The front should also protect the Southeastern U.S. from a tropical disturbance in the Atlantic that is forecast to make its way toward the Caribbean Sea over the next few days.

Don’t worry, though. As the cold air mass sinks, temps will rise back into the low to mid-70s by Saturday.

Conditions will stay dry, too. Aside from a very slim chance of rain — just 10% — Monday, there is no rain in the forecast for the foreseeable future.

Credit: WSBTV Videos

Very cold start to Thursday, sun will come out but today slow to warm up

» For a detailed forecast, visit www.ajc.com/weather.

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