The appearance of supernumeraries of high-order rainbows
in heavy rain showers is explored for rainbows up to of 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.