The days are getting shorter, the nights are getting cooler, and in early September the annual leaf change begins in the forests, meadows, and river banks of Colorado’s high plains.
The gold, red and orange tones of Colorado’s famous aspens, which stretch across the mountain slopes between Steamboat and Silverton, are an unforgettable sight.
Typically, the colors reach their peak in Colorado’s northern mountains — the Park, Mummy, Never Summer and Rabbit Ears product lines — throughout the month of September. The Central Mountains — the Flattops, Gore, Sawatch and Front Ranges — peak in the last week of the month. southern mountains — San Juans, Sangre de Cristo, Wet and Spanish Peak mountain ranges – peaking in the first and second weeks of October.
Leaves change color each fall when they stop photosynthesizing. As the green chlorophyll fades, yellow pigments become visible, leaving behind the colors we see on aspens, poplars, and other deciduous trees.
What influence does the weather have on autumn colours?
According to the U.S. Forest Service, the amount and brightness of colors in a given fall season depend on various weather conditions.
The most important influences before and during the loss of chlorophyll in the leaves are mainly temperature, humidity and the health of the trees.
“A sequence of warm, sunny days and cool, fresh but not freezing nights seems to produce the most spectacular plays of color,” the forestry administration explained.
Rain and wind can cause leaves to drop prematurely, shortening the display season. In addition, early fall snowstorms can similarly damage tree leaves by weighing them down and making them more prone to falling off sooner.
What is the monthly forecast for the start of fall foliage coloring in September 2024?
The National Weather Service’s monthly temperature forecast for September 2024 shows that most of the western side of Colorado will see temperatures 60-70% above average. In the eastern Plains, the chance of above-average temperatures for this month is 50-60%.
According to the National Weather Service’s monthly temperature forecast for September, temperatures in the 60s–70s are forecast for most of Western Colorado, including the state’s mountainous regions.
At the same time, the monthly precipitation forecast for September shows that in about 75% of Colorado, including almost all mountain regions, the probability of below-average precipitation is 40-50%.
The National Weather Service’s monthly precipitation forecast for September 2024 shows that about 75% of Colorado has a 40-50% chance of below-average precipitation. In the northwest corner, the chance of below-average precipitation for that month is 33-40%.
Following the Forest Service’s “relaxed rule,” above-average temperatures and below-average rainfall in 2024 could result in beautiful fall foliage coloring.
