Rainbows by elliptically deformed drops. II. The appearance of supernumeraries of high-order rainbows in rain showers

The appearance of supernumeraries of high-order rainbows in heavy rain showers is explored for rainbows up to order five (p=6). This is done by using a combination of the ray-theory-based first-order Möbius approximation for high-order rainbows with the Airy approximation of the rainbow radiance distribution. We conclude that supernumerary formation of rainbows of order three, four, and five is possible in natural rain showers. Supernumeraries of the third-order and fourth-order rainbows are preferentially formed near the bottom of these rainbows. A strategy for observing supernumeraries of high-order rainbows is proposed.