Cloud formations impress me, but then I am perhaps easily impressed. This is a very dramatic formation of altostratus clouds heralding the arrival of a cold front in Florida. I have the image both in color and in B&W — both are dramatic — but I like the impact of this one best. It scales to a very large print — 23×24 at 200 dpi, or nearly 2 feet x 2 feet if you like the poster effect of 100 dpi. See the full image in my gallery here.