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Many of us admire the stunning display of fall foliage in other parts of the country, where trees burst into shades of red, orange, and purple as the seasons change. Here in Houston, however, our leaves often turn a dull brown, or at best a pale yellow, and we rarely see the rich hues found elsewhere. So, why don’t we experience such a colorful spectacle?
Part of the reason is the types of trees we have - such as oaks, which aren’t as vivid as maples, but the main factor is our weather. I put together a video explaining why and how our leaves change color. You can watch it here:
The transformation of leaves in the fall is rooted in science. Chlorophyll, the green pigment in leaves, captures sunlight, water, and carbon dioxide, which plants and trees use to produce food during the growing season. This is why leaves appear green.
As the season shifts to fall and the sun’s angle lowers, the intensity of sunlight decreases. When this happens, cells begin to form at the base of the leaf, cutting off the flow of fluids. At this stage, photosynthesis comes to a halt.
It’s important to note that during the growing season, colors like green, yellow, and orange are all present in the leaf, but green dominates due to the constant production of chlorophyll. When chlorophyll breaks down and production stops, the yellow and orange pigments are revealed. Vibrant reds and purples emerge only when conditions are just right.
Without a distinct change in seasons, leaves often shift from green directly to brown. When temperatures remain too warm, fall colors become muted, which is our biggest issue. This October alone, we experienced eighteen days in the 90s, including five record highs. It’s fair to say our fall season often feels like a transition from hot to not-as-hot.
There have been years when early, strong cold fronts brought cooler days, more sunshine, and crisp nights, which made our leaves more vibrant. Unfortunately, 2024 has not been one of those years.
Precipitation plays a significant role as well. When the weather is dry, as it has been here since August, fall colors tend to be muted and delayed. I have friends in Michigan who shared with me that their fall colors were less impressive this year due to dry conditions.
However, with the perfect amount of rain at the end of summer and into early fall, the change in leaf color can be spectacular!
Meteorologist Evan Fisher is the founder of Explore Fall, an innovative fall foliage forecast. Fisher harnesses the power of artificial intelligence to predict the vibrancy of leaf colors across the country. For a deep dive into how he uses A.I. for these forecasts, check out the Off the Radar Podcast, which covers all the details.
Explore Fall has compiled fall foliage data dating back to 1991, and the image below shows the average peak dates for fall colors.
Zooming into southeast Texas, the graphic reveals insufficient data from The Woodlands to the coast, highlighting that our region rarely experiences a vibrant display of fall foliage. However, late November provides the best chance for some color change in areas like Conroe, Huntsville, and Livingston.
The Explore Fall forecast extends through November, and while much of the country has already moved past its peak, Houston is just beginning to reach it. Most of southeast Texas is expected to see moderate color, while areas along the coast will likely experience low color. So far, I’ve only spotted hints of yellow in our leaves. If you’ve captured a beautiful fall photo, please share it with me at click2pins.
