WASHINGTON CITY — Brian and Liz Baker have been self-admitted sky watchers for over six decades. But around noon on Sunday, they saw something in the skies above Washington Fields they say they have never seen: a band of prism colors.
At first, they thought they saw a sun dog – a refraction of light through ice crystals.
But it was something much rarer than a sun dog. They were looking at a fire rainbow.
“I’ve only ever seen this one fire rainbow in my 67 years of sky watching,” said Brian Baker, who supplied the images to St. George News.
The Bakers’ bedroom window overlooks a field directly west of Staheli Farms, and Brian said his wife was looking out at the sky when she noticed something.
“She mentioned to me that, ‘I can’t quite figure out what I’m seeing in the sky’ and asked me to take a look, ” he Baker said. “The colors were remarkable. The hues became more and more brilliant and then faded quickly. It was visible maybe for one to two minutes and then disappeared from sight. We just sat there thinking we might have missed it if Liz hadn’t been looking out at just the right time.”
According to meteorologists and climate scientists, a fire rainbow is neither a rainbow nor made of fire. The actual scientific term for it is “circumhorizontal arc” and it’s created by light from the sun reflected like a prism through clouds.
However, the reason people don’t just see a fire rainbow every day is it needs to be a certain type of cloud and the sun also has to be at a specific angle in the sky.
That said, Darren Van Cleave, the meteorologist in charge of the National Weather Service’s Salt Lake City Office, told St. George News that he wouldn’t call fire rainbows “rare.”
“We get this type of question every few months or so on our office social media, so I would say that it is uncommon but not rare,” Van Cleave said. “They are certainly beautiful and a treat to witness.”
Fire rainbows don‘t appear unless two things are present: cirrus clouds, which look wispy and thin like white hair in the sky, and the sun at a high position in the sky at an angle of 58 degrees or higher.
Cirrus clouds are high in the atmosphere and consist of ice crystals. Even on a triple-digit day below, it can be between minus-4 and minus-40 degrees so ice is possible up there. That’s also why condensation and exhaust from jet planes flying over St. George form contrails.
Light from the sun, when it is high in the sky, enters the ice crystals and is refracted just as it would be through a prism or through sprinkler water. Light is separated into its component colors.
What separates fire rainbows from actual rainbows is they are formed by light passing through ice, rather than water droplets. Its colors also tend to look more like pastel colors to the naked eye.
Sunday produced the right conditions. The sun at noontime Sunday in Washington City, according to sun-direction.com, was around 61 degrees and there were cirrus clouds in the sky. Weather experts say cirrus clouds are most commonly observed during the late spring and early summer months.
Sun dogs are also formed by ice crystals high in the atmosphere but are different from a fire rainbow in that they appear closer to the sun in equal positions. They can also form a complete circle, becoming a sun or moon halo.
Sun dogs are also much more common and can usually be seen up to 24 hours before a rainstorm when a lot of moisture is in the air. If it’s going to rain tomorrow and one knows where to look, they can see a sun dog.
Fire rainbows and sun dogs are just two of many types of atmospheric optical phenomenons formed by a combination of sun or moonlight, and some form of water in the air. Moon dogs, moonbows, double rainbows and halos have also been seen in local skies recently.
But for the Bakers, they may not forget soon seeing a fire rainbow on a sunny Sunday. And they say they have loved everything they’ve seen in the sky since moving to Washington Fields from Draper in the spring of 2023.
“We’ve fallen in love with the place, its people and especially the ever-changing skies. Whether it’s hot air balloons rising, beautiful cloud formations against a clear blue sky, a double rainbow or SpaceX rocket launches, the heavens in Southern Utah can be nothing short of magical.”
Photo Gallery
National Weather Service chart describes the features of sun halos, sun dogs and sun pillars, date not specified | Image courtesy of National Weather Service, St. George News Photo shows a "fire rainbow" or circumhorizontal arc above Washington Fields, Washington City, Utah, June 9, 2024 | Photo courtesy of Liz and Brian Baker, St. George News Photo shows a "fire rainbow" or circumhorizontal arc above Washington Fields, Washington City, Utah, June 9, 2024 | Photo courtesy of Liz and Brian Baker, St. George News Photo shows a "fire rainbow" or circumhorizontal arc above Washington Fields, Washington City, Utah, June 9, 2024 | Photo courtesy of Liz and Brian Baker, St. George News Photo shows a "fire rainbow" or circumhorizontal arc above Washington Fields, Washington City, Utah, June 9, 2024 | Photo courtesy of Liz and Brian Baker, St. George News A halo around the sun seen above Washington City, Utah, May 31, 2023 | Photo by Vin Cappiello, St. George News A double rainbow imaged above Washington Fields, Washington City, Utah, date not disclosed | Photo courtesy of Liz and Brian Baker, St. George News
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