Everything you need to know about fire rainbows
What's the story
Circumhorizontal arcs, also known as fire rainbows, are created when sunlight refracts, or bends, through the ice crystals in high-altitude cirrus clouds.
This refraction produces a spectrum of colors that appears as a brilliant, horizontal rainbow.
This article details the thrilling experience of chasing these elusive beauties in the sky, emphasizing the importance of planning, timing, and finding the perfect vantage point.
Basics
Understanding circumhorizontal arcs
Circumhorizontal arcs, unlike regular rainbows, occur when sunlight refracts through ice crystals in cirrus clouds.
Since they can only be seen when the sun is at least 58 degrees above the horizon, they are restricted to specific latitudes and times: primarily late spring to early fall in mid-latitude areas.
Understanding these requirements is key to successfully planning a trip to witness this marvel.
Spots
Best locations for viewing
Fire rainbows require specific conditions: cirrus clouds and sunlight at least 58° high in the sky.
They're most visible in places with clear skies and minimal pollution.
Think the American Southwest, parts of Australia, and South Africa.
Since pilots report them frequently, perhaps taking a flight over these areas might increase your odds!
Schedule
Timing your expedition
Spotting a fire rainbow is all about timing. May to August is prime time because of the high angle of the sun.
Go for a noon hike to catch the sun at its highest point.
Use weather forecasts for clear skies and sun position charts to pick the perfect day, and you might just get lucky to see this rare phenomenon.
Gear
Equipment recommendations
To effectively photograph this ephemeral phenomenon, some gear preparation is also necessary.
A high-quality camera with manual settings is crucial for adjusting exposure settings to accurately capture the vibrant colors.
Polarizing filters are also beneficial. They enhance the contrast between the bright colors of the arc and the blue sky background by minimizing glare from the reflective ice crystals in the cirrus clouds.
Precautions
Safety tips for aerial expeditions
Your safety should always be the number one priority during any aerial adventure chasing fire rainbows or other phenomena.
Ensure you select reputable aviation companies with seasoned pilots who are well-versed in local weather conditions and airspace rules.
Always wear the provided safety equipment by operators, including securing seat belts during flights, whether you're on small private planes or helicopters specifically designed for sightseeing.