I did chase that gnarly sand wall and it was great. (shot on slide film) I love to drive right up to the edge of the sand wall and look up, and shoot so I can see the edge where the sand meets the clear sky, and then put safety glasses on and let it roll over me. Sand storms have such a dramatic look. Last night I got to do the edge twice. The first time it came over, I shot it, then drove north to outrun it, then hit it again to the east. Rad.
Following the sand wall of course are thunderstorms. So after that there was some lightning to be had. Rain came later as well. The lightning was not as strong as other monsoon storms I have seen; the sand wall was the spectacular feature lastnight.
Now...if only blowing sand made our sunsets blue like it does on Mars. That would be a picture!