Fire + Tornado = Oh Jeez
So I've seen a tornado form, and, like an idiot, just stood there staring at it -- until it started moving towards me, at which point I ran, and felt the wind pushing at my back, until I was about a half mile away. That was an exhilarating (and scary) experience; the tornado was fascinating and strange, like the winds had become a creature. A creature that, unfortunately, might kill me.
So today I bring you, via the Bad Astronomy blog, a fire tornado that occurred near Mauna Kea in Hawaii. This happens when a fire itself causes a dust-devil-like effect due to air pressure differentials -- the fire then gets sucked up into the tornado funnel, and all Hell breaks loose (hah -- see what I did there?). Here's the first video posted by Bad Astronomy; my favorite part is towards the end when a fire truck heads towards the fire tornado, spraying water -- because, yeah, this could get out of hand.
This really is a fantastic demonstration of how microscale weather works. Imagine: a fire starts. As the air is heated above the fire, it rises, and the upward motion can be very strong. This leaves a lower pressure spot at the fire, and the air from outside the fire rushes in to fill the gap. The air is very turbulent, and as the inward-moving air from one side hits air coming in from the other, swirls can form. These get amplified by the constant gale of air, and rotation on a larger scale can get started and sustained. The whirlwind gets pumped by the hot air rising, and the next thing you know you’ve got a full-blown tornado of fire.
Read the rest for more on the science, and more links to fire tornado videos. Yes, there are more. Also, read the comments for interesting stories of that particular storm, and various good arguments that this is in fact a dust-devil rather than a true tornado.