Double rainbow lights up Vancouver skies

A double rainbow, led by one vivid, wide, primary rainbow, was seen in winter skies in Vancouver. (Courtesy: Laura Duhan-Kaplan)

Those in Vancouver dreaming of a white Christmas might be disappointed to learn there’s no snow in store this season, but the weather gods did offer something else over the weekend as consolation.

The day before the winter solstice – the shortest, and thus darkest, day of the year – the skies were unusually bright and filled with vivid colour as a stark set of rainbows appeared.

Social media users throughout the region were quick to post their prized shots online. Some images showed a detailed rainbow with another, less vivid rainbow beside it, while others had shots of just the one, wide arc.

"It was a rainy day, but the clouds broke at sunset, so I stepped out to enjoy it," said Laura Duhan-Kaplan, a Vancouver resident whose video of a thick, bright rainbow emerging from grey clouds garnered much attention online.

"When I turned the corner onto Main Street, I saw in the sky what looked like a painting of Ezekiel’s vision of heaven. A glowing rainbow, exceptionally wide and bright beaming out of glowing clouds," she said.

Duhan-Kaplan said she called her husband and her son to tell them to step outside, and look north. On Main Street, the colourful phenomenon was bringing strangers together in a way she hadn't seen before, she said.

"A random man at the bus stop said, 'Isn’t it amazing how these things happen? Just so, at special times.' And he told me a story important to him, from years ago," she said.

According to the U.S. National Weather Service, rainbows manifest when sunlight enters a suspended raindrop and gets refracted. Some of the light is reflected by the internal mirror-like surface of the raindrop, and refracted back out the raindrop towards the person who is viewing it.

For a double rainbow to occur, a part of the ray is reflected again along a different path inside the drop, causing it to exit the droplet at a different angle. This secondary rainbow has its colours reversed from the first and, because further reflection means a longer path for the light to reach the observer, it is often much fainter.

To be able to witness a rainbow, the National Weather Service says a viewer needs to be standing with the sun to their back, and the rain in front of them. The sun needs to be in a certain position above the horizon, and the sun's rays must be hitting the raindrops to create the rainbow.

Those who missed the weather phenomenon the first time around might be luckier in weeks to come. While snow is still yet to make an appearance, the wet weather is set to continue throughout the Christmas period.