Amidst a downpour Friday, a trail of white smoke climbing from the foothills in Azusa was an ominous reminder of the Colby Fire earlier this year.
The smoke began to rise after a large boulder rolled down the hillside, likely due to the heavy showers.
Fire officials said the Colby Fire, which began in January, was still smoldering under the bolder.
When the boulder moved, the rain put out the fire and caused the smoke.
About 2,000 acres were burned in the Angeles National Forest as a result of the Colby Fire.