I suspected as much...even though Cali natives have assured me that these fires are not uncommon, I figured there was something else going on here.
There is no doubt that most of these type of wild fires do have a human cause and are sometimes the result of deliberate arson, but are more likely as the result accidental human actions; improperly extinguished camp fires, both legal and illegal, lit cigarette butts thrown from cars, fireworks, fire pits or even fire places where burning embers light very dry and highly combustible tinder along with home owners and of course government land management policies that no longer allow the clearing of brush and dead wood, the creation of fire breaks, etc. And yes, some are caused by lightening but that is from what I understand is rather rare and this doesn’t seem to be the case with the “wine country fires”.
But one of the other causes, as seems likely in these most recent fires seems to point to downed power lines and faulty electrical equipment.
There were very high winds on the night when the fires first started and many reports of sparking power lines and exploding transformers shortly before the first reports of the brush fires that would soon turn in raging infernos.
http://www.latimes.com/business/la-fi-utility-wildfires-20171017-story.htmlhttp://www.sfgate.com/bayarea/article/From-lighting-to-foul-play-what-causes-6511859.php