A digital tornado

I have never seen a real tornado. I hope I do in the future, but when stock photography was a viable way to earn an income, I digitally created several tornados and they sold quite a bit. I found this dilapidated house in the American Southwest a number of years ago, and then I combined two stormy sky photos in Photoshop to create the background. I drew the shape of the funnel by using the lasso tool and feathering the edge of the selection by 30 pixels (Select > modify > feather). To make the clouds inside the funnel appear to be spinning, as they do in a real tornado, I pasted storm clouds into the tornado selection and used Edit > transform > scale to compress them. In other words, I took the top middle handle of the selection box and moved it down without holding the shift key (which would have maintained the correct proportions). The compressed clouds then had the appearance of horizontal streaks, which is what I wanted. Finally, I added the lightning because electrical activity is often associated with violent storms. To combine the lightning and the clouds, I used the 'lighten' blend mode in Photoshop.