As days grow shorter and temperatures cool, trees prepare for winter by shutting down food production. This process is called leaf senescence, the aging and eventual death of leaves.

Chlorophyll, the green pigment that helps leaves make energy from sunlight, begins to break down. As it fades, the brilliant reds, oranges and yellows that were hidden all summer are revealed. Eventually, leaves dry out, detach and fall, conserving the tree’s energy until spring returns.

The colors you see during leaf senescence come from different natural pigments. Carotenoids are responsible for golden yellows and oranges, while anthocyanins give some trees their deep reds and purples.

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The balance of these pigments, and how strongly they appear, depends on both the tree species and the weather. For example, bright sunny days help boost anthocyanin production, leading to more vivid reds, while cloudy or warm stretches may leave the landscape looking more muted.

Weather plays a big role in how leaf senescence shows up each year. Warm autumn days with crisp, cool nights can lead to especially vibrant colors, while drought or an early frost can cause leaves to turn brown and drop quickly.

In other words, the weather you experience in the weeks leading up to fall can determine whether you get a fiery foliage show or a more subdued one.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.