A cold front was on the western horizon and I needed to paint quickly to capture the cloud before it passed me by! The leading edge had some convective elements that were much newer and brighter cloud due to their small droplet size. The older frontal cloud elements were darker and much more gray. The gravity waves ahead of the front revealed strong westerly winds aloft. The surface winds were also westerly so only speed wind shear was evident with this cold front - although it produced severe convection the day before when it crossed the Nickle Belt. There was even a tornado warning issued. In any event, showers would arrive along the front about an hour after I finished.I enjoy painting on panels. It forces the use of more paint. Noticed I used two palettes for the first time ... to use more paint and to keep the colours clean!