Can weather forecasters predict rainbows? © Moron Eel

Can weather forecasters predict rainbows?

"Somewhere, there might be a rainbow..."

Asked by: John, Southampton


A rainbow is created when sunlight splits into various colours as it enters raindrops. These rays then bounce off the interior and re-emerge at slightly different angles, depending on their colour. Seeing a rainbow thus depends on where you’re standing relative to the Sun and the raindrops. So while forecasters can predict the conditions of patchy cloud and showery conditions that make a rainbow likely, they can’t tell if you’ll be in just the right place to see one.

Why can’t we reach the end of a rainbow? © Getty Images


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