Meteorologists solve 'Strange sky' mystery which left onlookers awestruck
A colourful cloud phenomenon which lit up the skies in Costa Rica recently has left witnesses mystified.
The spectacle was spotted on September 16 in the sky, and spanned between several Costa Rican cities including the capital San Jose.
Observers eagerly shared pictures on social media with the hashtag #ElcieloExtraño, the Spanish for "strange sky."
Resident Joey Petit told ABC News that he and his family were celebrating Independence Day festival when his 11-year-old son, Ariel Joseph Petit first noticed the strange cloud.
"He immediately grabbed the camera and started taking video and photos," he said.
"We were just so amazed. We had no idea what it was and we'd never seen anything like it."
Costa Rican, Jessie Montealegre, said she was also was amazed by the multi-hued phenomenon.
“You guys, I have never seen anything like this,” said Montealegre as she recorded the cloud over Escazu, Costa Rica.
The skies “opened up as if it were the end of times,” she wrote on YouTube.
The cloud is known as a "pileus" or "cap cloud" and typically occurs in rain showers when the sun's angle is low on the horizon, according to meteorologists.
"It's caused by the sun's light being refracted by water droplets and ice crystals in the cloud," said, Eladio Solano, a meteorologist with Costa Rica's National Meteorological Institute, according to Costa Rica media outlet Teletica News.
These clouds can usually be spotted during the early stages of thunderstorm development and they signify that a storm is rapidly gathering strength.
You have to be quick to spot them as they typically don't last very long.