This is the final result I settled on for the fore tornado. It look more than half a day to accomplish with much experimentation. What can’t be seen in this still shot are the flames licking upward and the funnel spinning around the flames. The fire is done with displacement fractal noise and lots of glows.
The tornado had a particle generated center, but I abandoned that attempt. I had to try every variation of blending mode to get just the right amount of fire visible through the spinning clouds. I figure out how to use a gradient map to fade away the top of the tornado into the clouds.
The balloons were separated from the background and all the clouds now spin around the tornado. I also painted a smear of a cloud at the top of the tornado and added displacement to that to get it to spin like the other clouds. Volume was added to the balloons with a depth map but that effects is subtle. I probably could accomplish far more depth in the balloons if I separated them into three separate planes. I decided the extra work wouldn’t be worth it. The shot is over in just over a second.