15-mile-long cloud of ladybugs over California appears on weather radar

A massive cloud of ladybugs known as a "bloom" was over the San Gabriel Mountains of California and appeared on weather radar. Forecasters at the National Weather Service office in San Diego posted a gif. A massive cloud of ladybugs known as a "bloom" was over the San Gabriel Mountains of California and appeared on weather radar. Forecasters at the National Weather Service office in San Diego posted a gif. Photo: National Weather Service Photo: National Weather Service Image 1 of / 1 Caption Close 15-mile-long cloud of ladybugs over California appears on weather radar 1 / 1 Back to Gallery

Forecasters working the Tuesday evening shift at the National Weather Service's San Diego office were confused.

A large echo indicating rainfall showed up on weather radar over the San Gabriel Mountains near the town of Wrightwood, Calif. but there were no clouds in the sky.

"The radar was showing there was something out there," says Mark Moede, a forecaster with the NWS. "We looked at the satellite image but there weren't clouds that size in the area."

A few calls were made to weather spotters in the area, and finally one of them said, "ladybugs!"

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 turns out a massive cloud of ladybugs, called a bloom, measuring 10 miles wide and 15 miles long was flying around above 5,000 feet elevation.

"He said it's an annual bloom that happens around this time of year," says Moede.

In California, the beetles are known to winter in the Sierra and gather in huge masses in valley areas in the spring to feed and mate, usually in the same places year after year.

Amy Graff is a news producer for SFGATE. Email: agraff@sfgate.com.