Higher temps delay fall foliage

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Blacksburg, Va., Nov. 7 – Hokie Colors: The trees around Terrace View Apartments took longer than usual to change color this year, but they still reached their peak levels. Photo: Matthew Atkins

by Matthew Atkins–

The New River Valley is a popular area to see fall colors on the trees, but outdoor enthusiasts didn’t get the foliage they had hoped for this season.

According to the SmokyMountains.com foliage map, the NRV didn’t see peak colors until Nov. 5 of this year, a delay caused in part by higher temperatures.

“With weather, what we saw here in Virginia is that we had one of the warmest falls and warmest summers, period,” said WDBJ meteorologist Ian Cassette. “A lot of it had to do with how mild our nights were. We were seeing some pretty warm days, but we were seeing a lot of really  warm nights as well.”

Cassette says lower temperatures are what typically leads to fall color. When temperatures drop, green chlorophyll exits the leaves, leaving orange, red and yellow behind.

That didn’t happen as much this year. Cassette says that the area set records for overnight lows, reaching up to 70 degrees when the temperatures should have been in the 50s.

This warmer season directly affected the leaves, as last year’s peak colors had already passed by early October. While the color variation can change from year to year, some trends show that higher temperatures are here to stay.

According to U.S. Climate Data, the average temperature in Roanoke for the month of October has risen three degrees over the past decade, while the average low temperature has risen nearly four degrees.

Cassette says that those numbers go back even further.

“Over the last 25 years, Roanoke, looking at the facts, has gradually seen slowly warmer overnight lows during the fall months,” Cassette said. “That may actually end up being a pretty big factor towards getting those ideal conditions to see the fall colors here.”

Although the temperatures play a big role in fall colors, other factors have a hand as well. Cassette listed the amount of rain and number of tropical systems in the area as contributors to this year’s delay in color.

Whether the foliage will get back on schedule next year is unknown, but higher temperatures are certainly having an effect.