Fall foliage forecast: Warm air may hinder emergence of bright colors in East

28 Small Towns Across America With the Most Beautiful Fall Foliage

By Jillian MacMath, AccuWeather.com Staff Writer

Weather conditions over the past few months have laid the foundation for a vibrant display of fall colors in the East, but temperatures in the coming weeks will be the determining factor, experts say.

"I think, overall, that trees are going into the autumn in good physiological condition," Dr. Marc Abrams, professor of ecosystem science and management at Penn State University, said.

"Assuming that we get a normal cooldown in late September to mid-October, the fall colors should be very good."

Beautiful Fall Foliage
See Gallery
Fall foliage forecast: Warm air may hinder emergence of bright colors in East
(Photo: Shutterstock)
(Photo: Getty Images)
(Photo: Getty Images)
A leaf floats in water in Regent's Park on October 21, 2014 in London, England. Despite weather warnings issued by the Met Office for high winds and rain off the back of Hurricane Gonzalo, those predictions didn't materialise in London. (Photo by Dan Kitwood/Getty Images)
NEW YORK, NY - OCTOBER 29: An End of road sign is seen overgrown in bushes two years after Superstorm Sandy damaged much of the area on October 29, 2014 in the Graham Beach neighborhood of the Staten Island Borough of New York City. Huricane Sandy was recorded as the deadliest and most destructive hurricane of the 2012 Atlantic hurricane season. It caused over $68 billion in damages, and hundreds of people were killed along the path of the storm in seven countries. Today marks the two-year anniversary of its storm surge hitting New York City and the surrounding area which flooded streets, tunnels and subway lines and cut power in and around the city. (Photo by Andrew Burton/Getty Images)

To date, the best displays are expected to be visible in New England, upstate New York and the Great Lakes states, but temperatures in the coming weeks could stunt the development of the East's traditional bright colors.

"The upcoming weather is very important," Abrams said.

From late September to mid-October, a cold snap paired with dry conditions helps to bring out the vibrant reds, yellows and oranges.

"We want to avoid warm, wet and windy weather during that time," he said.

According to Abrams, bright colors are also in the offing for the Appalachian Mountains and as far south as North Carolina and Tennessee.

2015 US Fall Forecast: Fire Danger to Worsen in West; September May Yield Tropical Impact in South
The Best National Parks for Fall Foliage
Ten Best Fall Foliage Trips in the US

Three primary factors influence the intensity of foliage colors during the fall season: photoperiod, cool air and water stress.

"The proper photoperiod is upon us," Michael Day, associate research professor of physiological ecology for the University of Maine, said.

"In the Northeast, trees have had above-average late summer water stress, but we are yet to have a substantial cool period over much of our area," he said.

However, forecasters predict autumn's chill may be delayed this year, proving to be bad news for leaf-peepers planning vacations around the seasonal sights.

"A very warm pattern will be found across much of the central and eastern United States through the end of September, particularly in the Great Lakes, Appalachians and Northeast, where temperatures will average well above normal," AccuWeather Meteorologist Anthony Sagliani said.

"Through the first half of October, we expect a generally warm pattern will remain in place. There are a couple of signs for a cool shot or two, but any long-lived cold snaps appear unlikely," he said.

More from Accuweather:
Deadly Earthquake Rocks Central Chile
Gusty Thunderstorms to Drench Plains, Midwest
Families Flee as Floodwaters Rise in Sierra Leone's Capital

Read Full Story