Loud Booms Set Off Car Alarms in Eureka, California

Residents of Eureka, California were surprised last night by a series of loud booms that rattled homes and set off car alarms in the area. Some of the noises (four were reported in total) were accompanied by bright flashes of light.

Area residents reported the sounds via social media, with one Facebook user describing she could “see them out over the bay. Bright flash and then big boom.”

Another user noted the succession of booms were heard clearly near the vicinity of Summer Street, while another posted, “I live on union near Hawthorne. Big booms.Cops were a block away …now have dispersed.”

Writing for the Lost Coast Outpostblogger Hank Sims surmised the “best guess seems to be ‘industrial-grade fireworks,’ but we may never know for sure.”

According to the online meteorological resource Weather Underground, conditions in the vicinity of Eureka, CA, were clear on the evening of April 20th, with temperatures in the mid 50s.

Apart from the fair weather in the area, the bright flashes reported in conjunction with these observations bear similarity to descriptions of booms that accompany some upper atmospheric storms, which in 1977 and 1978 were determined to be one set of likely causes for a wave of booms reported along the northeastern U.S. coast. Under such circumstances, it is possible that weather systems off the coast of the Humboldt Bay might have been the source of the booms. For more information on this phenomenon, visit our page about “superbolts” and upper atmosphere storms.

Recent reports of loud booms accompanied by bright flashes in the sky were also reported near Port Douglas, Australia, in late March, 2015.

Image courtesy of Robert Campbell, U.S. Army Corps of Engineers Digital Visual Library.