‘Storm system’ turns out to be massive swarm of ladybugs

A 130km wide “blob” thought to be a massive storm system has instead turned out to be something completely unexpected and bizarre.

What looked like a massive storm on the way turned out to be a huge swarm of ladybugs. Picture: Supplied

A mysterious “blob” that appeared on the US National Weather Service’s radar wasn’t a rain cloud or a storm, but a massive swarm of ladybugs.

Meteorologist Joe Dandrea said the bug mass appeared to be about 130 kilometres wide as it flew over San Diego County in Southern California yesterday.

Mr Dandrea told The Los Angeles Times the ladybugs were actually spread throughout the sky, flying at an altitude of between 1500m and 2700m, with the most concentrated group about 16km wide.

After seeing it on the radar, Mr Dandrea said he called a spotter near Wrightwood in the San Bernardino Mountains, northeast of Los Angeles, to ask what they were really seeing.

“I don’t think they’re dense like a cloud,” he said. “The observer there said you could see little specks flying by.”

The large echo showing up on SoCal radar this evening is not precipitation, but actually a cloud of lady bugs termed a "bloom" #CAwx pic.twitter.com/1C0rt0in6z

— NWS San Diego (@NWSSanDiego) June 5, 2019

It wasn’t immediately known what type of ladybug was causing the phenomenon.

However, The Times reported that one type, the convergent lady beetle, migrates to higher elevations in the early summer to find food, according to the University of California Integrated Pest Management Program.

A large group of ladybugs is called a ‘bloom’. Picture: Supplied

“The large echo showing up on SoCal radar this evening is not precipitation, but actually a cloud of lady bugs termed a ‘bloom,’” the National Weather Service office in San Diego wrote, in a tweet that has had more than 1000 likes and retweets.