I’ve witnessed an automobile catch fire and explode. Nothing like in the movies, mind you, but the flaming interior didn’t look particularly inviting. I’ve also passed to within 40 feet of another flaming automobile, and the radiant heat was surprisingly intense, even through my vehicle’s windows were closed and I was moving, not stationary.
As a forest fire approached, I’d be concerned about the 15 gallons of gasoline located five feet from me.
BTW, if you’d like to know more, in addition to Maclean’s book (a practical ‘must read’ for everyone in forestry fire suppression), Google for “Mann Gulch” and you’ll see a number of links to information about that terrible day.