The Labor Day Weekend Williams Fire is now 100% contained and the entire San Gabriel Canyon is re-opened to the public, although Glendora Mountain Road and Glendora Ridge Roads are still closed while work crews clean debris.
The Forest Service has also released the cause of the fire – which was a bit surprising. Apparently a vehicle parked on top of some dry brush in a turnout. After being in a the sun for a while, the car’s body heated up enough that the undercarriage ignited the brush beneath it. To be honest, I didn’t even know this could happen – so next time you’re looking for parking at a crowded trailhead, make sure you’re over gravel and not anything that might catch on fire.