Weather Affects Color Intensity
Temperature, light, and water supply have an influence on the degree and the duration of fall color. Low temperatures above freezing will favor anthocyanin formation producing bright reds in maples. However, early frost will weaken the brilliant red color. Rainy and/or overcast days tend to increase the intensity of fall colors. The best time to enjoy the autumn color would be on a clear, dry, and cool (not freezing) day. ~Carl E. Palm, Jr.
Source: Environmental Information Series
|Both trees are next to each other, but the colors aren’t the same. ~Jendhamuni|