The animation below is a sequence of vertical cross sections that depict the development of precipitation ahead of and along a cold front. The surging blue mass represents colder air behind the cold front (solid blue line) while the yellow shading indicates the warm moist air mass ahead of the front.
Animation by: Hall
As the front advances, the colder air lifts the warmer air ahead of it (red arrows). The air cools as it rises and the moisture condenses to produce clouds and precipitation ahead of and along the cold front. In contrast to lifting along a warm front, upward motions along a cold front are typically more vigorous, producing deeper clouds and more intense bands of showers and thunderstorms. However, these bands are typically quite narrow and move rapidly just ahead of the cold front.