Plein air in French means outdoors ... pulling the spindly trunk of a lilac bush from bright green grass. Wispy clouds floated across a cerulean sky. With short strokes, purple flowers bloomed ...

above our chilly Great Plains air. Clouds will increase during Tuesday. A few patches of rain are possible Tuesday night and ...

Known as Kelvin-Helmholtz clouds, they form when a faster stream of air moves above rising air below. According to the Met Office website, Kelvin-Helmholtz clouds are "an extremely rare phenomenon".

In the skies over Champaign, Illinois, were wonky, wavelike clouds — reminiscent of the ... The thunderstorms were “elevated,” or rooted in mild air above the ground. The surface temperature ...