If you're into leaf-peeping, be patient because the picture-perfect bright red, orange, and yellow colors may be a bit delayed. Some scientists say the extreme heat over summer into fall could be to blame.
Merrie and Peter Lasky of California went on vacation the last two weeks of September to take in the colorful fall foliage, only to see most of the leaves on the trees were still green.
"We took a cruise that was called 'Fall Colors.' It's supposed to be this time of year that went from New York to Montreal," said Merrie.
"I think there was a little bit here and there," said Peter.
The couple's cruise took them to several stops in Canada and all along the East Coast including Newport, Rhode Island, Boston, Massachusetts, and Bar Harbor, Maine. They were especially excited about an excursion to Acadia National Park.
Peter said it was more of a see if you can find Autumn colors sort of trip.
"Where are they? Oh! Over there! There's a tree that's turning a little!"
Dr. Shawn Serbin with the NASA Goddard Space Flight Center has a background in forest ecology, plant physiology, and ecosystem science. He says high temperatures can create internal cellular damage in leaves impacting not only their color intensity but how long they stay on branches.
"That extreme heat can cause leaves to shrivel, and senescence sooner than you might expect."
"It's possible that with future climate change and with increasing temperatures in the summer and fall we may end up having more dull fall periods than we would like to see."
Serbin also expects there to be scientific studies to see if Canadian wildfire smoke has played a role in the vibrancy and timing of fall foliage since smoke particles can impact sunlight and therefore leaf photosynthesis.
The Old Farmer's Almanac says typically the second and third week of October are the peak times when leaves change color, but it does depend on where you live and your weather.
According to the U.S. Forest Service generally, leaves start changing color in late September in New England.
The Lasky's thought their trip's time and location were just right.
"It was all very nice. We enjoyed Acadia National Park and all of the tours that we took, but it could have been any time of the year," said Merrie.