"Out here there's the sky"--adventures in gray

"50 Shades of Gray," 9 x 12 watercolor, 140 lb. d'Arches cold press paper

How can you not live out here and not be enchanted by the skies? Willa Cather had it correct, and my motto has been "Out here there's the sky."
Today's ever-changing unsettled skies prompted this attempt. For me, it's an adventure in mixing grays--so many ways and tones possible with just a few colors--trying to match some of the tones I see in our clouds, and knowing, somewhere there's a sky like that. 
I'm always trying to figure out ways and colors to obtain some of those wonderful grays. There are about eight different colors used here, and none of them are labeled "Gray." That tube of paint seems dull to what I see overhead.