Fall officially begins September 22nd at 9:03 PM. The forecast, football, and all of the pumpkin spice goodies may be getting you in the spirit. The Northeast is in all of it’s glory when the trees start to show their beautiful colors. Like many things, the weather has a big influence on the vibrancy of the fall foliage.
Fall Science
Why do the leaves change color and fall? Chlorophyll production, which gives leaves that green pigment, begins as the tree comes out of it’s dormant stage during the winter. It traps sunlight, creating food for the plant/tree. The intensity of sunlight decreases as the growing season transitions to fall. Cells then form at the base of the leaf and stop carrying the sugary fluids to the rest of the leave. The sugars get trapped and new color pigments start production.
The shade of the leaves is determined by the production of chlorophyll. All year round greens, yellow, and oranges are all present in the leaf. During the spring and summer months, green dominants due to the tree’s production of chlorophyll. As the days get shorter, the sun angles lowers, and the temperatures begin cooling the tree stops making chlorophyll. The other hues of yellow and orange, red and purple are revealed before the leaves drop.
Temperatures Impacts
The weather influences the vibrancy and duration the foliage season. Ideally we want a nice mix of warm afternoons and crisp nights for a long, colorful fall. Abnormally warm days are often accompanied by warm nights and more clouds. This will mute the peak foliage.
Moisture Impacts
Rainfall from the summer and early part of fall is important. Moisture has more of an impact on the timing of the color change. The tree may just give up after a dry growing season. It has been stressed for an extended stretch. The peeping season is accelerated with the leaves quickly changing and dropping. Too much rain is problematic as well. The leaves will hang on well into the season. Winter events then become a threat and can suddenly bring a close to the season. In a perfect world, seasonable rainfall is needed for an on time vibrant color change.
There are other variables such as bugs and disease that can also influence the fall colors.
Fall 2022 Foliage Outlook
Experts are predicting an earlier than normal peak with muted colors. The leaf drop will likely come sooner as well. This prediction comes following one of the warmest and driest summers for eastern New York and New England. It wasn’t just the warm temperatures, but more so the scorching summer days. In Albany there were 22 days above 90 degrees; seven of those were at 95° or hotter.
The lack of rainfall stressed all plants. Summer is historically our wettest season. This summer ended with a deficit over five inches. The area’s moderate to severe drought could spoil the brilliant colors. The drought started well before the dry summer. Less winter was rather “snow less.” A significant snow pack was confined to northern Maine, the White Mountains, and northern Vermont. The soil quickly dried out in the spring with limited snow melt.
You may have already noticed some color change. The leaves have hung on as long as they can. Now the colors are starting to turn after the stress of a long hot and dry summer. Predicted peak fall colors will come during the first half of October for eastern New York and western New England. Columbus Day weekend might be one of the last good ones to go leaf peeping. That’s a few weeks ahead the typical peak. Central New York won’t be as impacted due to the lack of drought.
Climate change will likely bring more irregularity to foliage season. Summers are trending warm. Long wet or dry stretches are become more common. These trends could shorten the foliage season and only peak with muted colors.
