In the late sixteenth century, masters such as Cuyp, van der Neer, Ruisdael and Goyen began to paint the heavens not simply as a backdrop, but instead transformed them into a grand stage occupying up to 80 percent of the canvas. Here the painters let nature’s spectacular manifestations parade past. Sheet lightning, cloud vortices or the blazing heat of the sun exerted a great fascination on the public. At the same time the artists could cast their mountain, forest or river scenes in different moods. For this they studied the various weather phenomena very exactly, beginning long before science took note of them. The Wallraf is showing “Sunny with Cloudy Intervals” to 1 July 2018 in its Baroque section on the museum’s second floor.