What are the ideal conditions for having the best fall colors. Is it rainfall? Does this rain need to be in the Spring, Summer, Fall?

Fall coloration depends the amount of sunlight, temperature and amount of water during the fall season. The temperature during the time the chlorophyll production lessens is very important. Basically dry, sunny days with cool but not freezing nighttime temperatures are the most conducive to spectacular leaf color. During the warm days, the leaf can produce a lot of sugar. During the cool nights, the sugars are trapped in the leaves and eventually produce the colors of autumn. Late springs, dry summers or a very warm spell in fall will reduce fall coloration. When frost comes early, the colorful display may not occur at all.