Rare weather phenomenon spotted on Hilton Head Island. Did you see the fogbow?

Patricia Shapiro has been visiting Hilton Head beaches for about 30 years. Last week, she saw something she never had before: a fogbow.

“We were all like little kids. We were so tickled,” she said, describing the moment she and her husband first saw the muted, fuzzy colors at the Port Royal Plantation beach on Thursday.

The fogbow looks like a ghostly cousin of the rainbow. Both weather phenomena are caused by sunlight traveling through water droplets suspended in the air, according to National Weather Service Senior Meteorologist Neil Dixon. The water droplets bend and reflect the light, which forms colors.

The difference between the two starts with the size of the water droplets.

“For fog, they’re very, very small water droplets, and as the sunlight passes through (the droplets) and refracts in different ways, it results in the fog bow,” Dixon said. “It doesn’t have the vivid colors that you see with a rainbow.”

The fogbow is typically localized and lower to the ground than a rainbow, he said.

Dixon said fogbows aren’t that uncommon, but in his 25 years as a meteorologist he hasn’t seen one in person. The best chance at spotting one is in the winter or spring when there is frequently sea fog, which is caused when warm air flows over colder waters.

“If you do see one it’s certainly worth pausing and taking it in because chances are, it’s going to take some time before you see another one,” he said.