I’m switching things up a bit for today’s newsletter. Throughout the years at KPRC 2, I’ve received hundreds of messages from people asking about things they’ve spotted in the sky, whether it’s a unique cloud formation or a curious weather phenomenon. So, I figured, why not start building a library of answers to help explain what’s happening above us?
Take these incredible photos from ThompM, for example. He captured a stunning fogbow over Galveston’s west end and shared it on click2pins.com. If you ever snap a cool weather photo, send it over to us through Click2Pins, I’d love to see it!
Fogbows, explained:
A fogbow forms the same way a rainbow does, light bends, reflects, and scatters through water droplets, but there is a key difference. The droplets in fog are much smaller than raindrops, which changes how the light spreads out. Instead of the bright, well-defined colors of a rainbow, a fogbow looks pale or mostly white.
These misty arcs show up when sunlight shines through fog, often in coastal areas. But the fog can’t be too thick, or the sunlight won’t get through.
Because the water droplets are so tiny, fogbows look delicate and almost ghostly, earning them the nicknames “ghost rainbows” or “white rainbows.”
How a fogbow forms:
- Light Enters Fog Droplets – When sunlight (or moonlight) passes through a cloud of tiny water droplets, the light bends (refracts) as it enters each droplet.
- Reflection Inside the Droplet – Just like in a rainbow, some of the light is reflected off the inner surface of the droplet.
- Scattering and Diffusion – Since fog droplets are much smaller than raindrops (about 10 to 1,000 times smaller), they scatter light more evenly. This prevents the clear color separation we see in a typical rainbow.
- A Pale Arc Appears – The scattered light exits the droplets at the characteristic angle of a bow (about 35–40°). Because of diffraction, the colors blend together, creating a soft, mostly white arc instead of a vivid rainbow.
Have a weather question you want answered? Email me at ayanez@kprc.com.
