GATLINBURG, Tenn. — It definitely feels like fall and some of you may be ready to see some fall foliage.
The prolonged heat and drought from August through early-October has things looking green and summer-like in much of East Tennessee but experts are not giving up on a shot at decent fall colors.
The end of September is when East Tennessee historically starts enjoying its fall colors before they peak in mid-October.
The vibrancy of the colors depends on how much sugar is in the leaves.
Here's how it works: During the spring and summer, leaves act as a factory making the food necessary for the growth and survival of the tree. Chlorophyll is the main player in that process, and chlorophyll makes the leaf look green. In fact, there is so much chlorophyll that it hides the other colors present.
Inside of a leaf are other pigments that look yellow and orange but a couple of things need to happen for these colors to be revealed.
The first is day length. In the fall, shorter days trigger the tree to stop making food. Leaves are sealed off from the branches, and any extra sugars are left behind.
Next, you need a few cooler evenings. This confirms to the tree, that winter is coming and it's time to protect itself and go dormant. So it continues to seal off the leaves. It also helps turn the sugars left behind red and purple.
Finally, you need sunshine. Sunny skies burn off the chlorophyll faster than cloudy ones. As it disappears, the brilliant yellows, oranges, reds and purples are revealed and we see our fall colors.