It is not a Rainbow at all, although looking like, but an ice crystal halo. Ice crystals in Florida? Yes indeed, obviously they were over Florida in the high level Cirrus clouds. The Rainbow colors arise by refraction of sunlight in the prism-shaped Crystals. In the picture I recognize the so-called circumhorizontal arc. That is a colorfull halo form just below the sun, when those is high in the sky.