Thank you both.
The stormy skies are such great subjects to paint. I hope you do one and post it for us to see.
I don't go to art shows any more but this will be posted on FineArtAmerica shortly. As far as the difference doing it digitally, just visualize a brush moving the paint around the canvas instead of the circle you see. The brush reacts just the same as a traditional one, I just control the amount of paint, the color, the size of the brush and how much blending to do.