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
NPR:
"It was very strange because it was a relatively clear day and we weren't really expecting any rain or thunderstorms," . . . a NWS meteorologist in San Diego, tells NPR.