Along Highway 20 approx. half way between Marysville and Grass Valley, a bit west of the turnoff to Brown's Valley.
Highway 20 is a great 2 lane highway that runs between Ft.Bragg on the coast and Yuba Gap in the Sierras along I80. IR conversion by Lifepixel, the 720mm "regular" conversion.
At the end of a Spring photo day we stopped to photo this looming thunderhead at the junction of California's Central Valley and The rising Foothills.