One interesting feature of climate change, Professor Richard Primark said, is that the leaf peeping season could become longer as frosts are pushed out further and leaves hang on for longer periods of time.
“Trees detect the length of the day by measuring night temperatures and length of the night,” he said. “Nights longer in August, trees detect that and undergo color change. It’s possible the color changes will be longer and more extended. They’ll just hold those colored leaves for a longer period of time because the days are very sunny and mild temperatures and the frost is still many weeks away. So I think the prediction is the fall conditions are extremely variable and we might actually have a longer season of leaf peeping than in the past.”
That is mostly due to the change in the first frost.
Primark said in the 1950s and 1960s, the first frost usually came in late September. Now, it’s being pushed back to late October or early November. Usually the first frost puts the beginning of the end to the brightly-colored leaves. Now, leaves begin to change in late August, and if there’s no wind or frost, they can stay on far into November.