By December, the colorful fall foliage season has long passed in New England, the Rockies and even the Southern Appalachians. But in many places around North Florida, including St. Johns County, foliage colors occur for a couple weeks, depending on the cold weather science. Temperature, sunlight, moisture and soil conditions all contribute to the show. Dry, sunny autumn days with cool but frostless nights are best. No matter how subtle, we do have leaf color that’s ripe for viewing.