Tenaja Fire Spawns Eerie 'Fire Clouds': NWS

ESCONDIDO, CA — Dark clouds were visible from San Diego's North County Thursday due to a developing storm as well as heat from a fast-moving fire in nearby Southwest Riverside County.

The Tenaja Fire, which sparked Wednesday in the community of La Cresta in Riverside County, had grown to an estimated 2,000 acres Thursday and was just 7 percent contained, according to the Riverside County Fire Department.

The heat signature from the blaze generated pyrocumulus clouds Thursday afternoon, according to the National Weather Service in San Diego. The clouds form from rising air that results from intense heating of the surface by phenomena such as wildfires.

"Oftentimes, when a fire is really intense and the environmental conditions are favorable enough, you'll get essentially clouds forming right where the plume rises," Bruno Rodriguez, a meteorologist with the National Weather Service in San Diego, told the Los Angeles Times.

"Typically we'll see it on larger fires where the burning is more intense because you have more heat production, and therefore the increased heat production results in a stronger updraft to raise that plume higher and make it more likely to develop into a cloud at higher altitudes."

As of 2 p.m., there were no active fires within the Escondido city limits, according to the Escondido Fire Department.

Read more on the Tenaja Fire on Murrieta Patch.