In the South, it means the humidity abates, the nights are cool, the mornings crisp as you head for your car.
Where there is no such thing as 'transitional clothing'. In other words, I Have Nothing To Wear. Because it won't stay cool enough through the day to wear a sweater, even a short-sleeved one. It's a week away from October 1st, so linen capris look, well, silly. And it's really time to put the sandals away. But it's still too warm for most pants and I just can't wear khakis every day.