UW-Madison captures video of 'fire rainbow' - WXOW News 19 La Crosse, WI – News, Weather and Sports |

UW-Madison captures video of 'fire rainbow'

Posted: Updated:

MADISON (WKOW) -- This week UW-Madison shared a video and photo of what experts are calling a rare rainbow imposter showing up in the sky on Thursday.

UW meteorologists say a 'fire rainbow' is an atmospheric phenomenon known as a circumhorizontal arc, often mistaken for a rainbow because of its colors.

"They're not all that common but they're not completely rare, either," says Steve Ackerman, director of the UW-Madison Cooperative Institute for Meteorological Satellite Studies. "I've only seen a half-dozen in my lifetime here in Madison."

Rainbows form when sunlight reflects off water droplets in the atmosphere, but circumhorizontal arcs require a certain number of ice crystals of a particular shape to form. Experts say as sunlight passes through a cloud full of ice crystals, the light bends through and separates into the bright spectrum of colors.

Fire rainbows occur only when the sun is 58 degrees or higher above the horizon, which means they're only visible in the U.S. in the six weeks before or after the summer solstice.

Most Viewed Content

Stories
Videos

What's on WXOW tonight

Powered by WorldNow
All content © Copyright 2000 - 2014 WorldNow and WXOW. All Rights Reserved.
For more information on this site, please read our Privacy Policy, Terms of Service and Mobile Privacy Policy & Terms of Service.

Persons with disabilities who need assistance with issues relating to the content of this station's public inspection file should contact Administrative Assistant Theresa Wopat at 507-895-9969. Questions or concerns relating to the accessibility of the FCC's online public file system should be directed to the FCC at 888-225-5322, at 888-835-5322 (TTY) or at fccinfo@fcc.gov.