Typically, throughout the month of October park visitors can expect to find good fall color along the Blue Ridge Parkway. Leaves will begin changing first on the highest peaks and conclude in the lower elevations. Whether classified as "spectacular" or simply "average," the leaf color display will nonetheless be pleasing to the eye somewhere along the Blue Ridge Parkway. We are very fortunate in that the most varied fall color, as well as the longest lasting, occurs in the southern Appalachians, where a dozen or more species of trees may change color at slightly different times over the longer fall season.
There is no simple formula for predicting fall color. The intensity of fall color and time of peak color vary and are determined by complex environmental factors, as well as the genetic makeup of the plants themselves. These factors vary from plant to plant and from region to region. However, with ideal weather conditions such as bright sunny and cool days in the fall, one can expect slightly above average leaf color. The "best" fall color for an area occurs during the shortening days of autumn when days are bright, sunny and cool, when nights are cool but not below freezing, and when there has been ideal rainfall. Adequate rainfall also keeps the leaves on the trees longer and enhances the color. Wet, cloudy, warm weather or exceptionally low temperatures in early fall tend to mute the much anticipated autumnal display. We don't yet fully understand all of the complicated actions - and even more complicated interactions - involving pigments, sunlight, moisture, chemicals, hormones, temperatures, length of daylight, site, genetic traits, and so on that make for a perfect autumn color display. As research probes deeper into the basics of plant life, we will understand more about the processes that color the autumn landscape.