My niece was raised in Hawaii where rainbows can seen daily during the wet season ...
According to her, a rainbow is a celestial path the Hawaiian Gods & spirits use to visit earth ...
Each color represents something spiritually, but she can't remember them all except that the first one means transformation ...
She says she's also seen 2 round rainbows in a span of almost 30yrs; rare occurrence that was explained to her by an elder aunt of ours the 1St time, but she also forgot it's meaning ...
Sorry, but smacking her upside the head to help her remember is futile - she's old like me! ...
Anyhoo, wish I could've offered more ...