In A Storm during Haymaking, nineteenth-century French painter Jean-Francois Millet recorded these farm labourers hurrying to gather their hay as a towering Cumulonimbus rolled in, threatening their harvest.

Cumulonimbus are tall, powerful storm clouds that can indeed bring intense weather. They often produce heavy rain, thunder and lightning, and strong, gusty winds. In more severe cases, they can cause hail, flash flooding, even snow or ice pellets in colder conditions.

Millet’s Cumulonimbus is ominously dark as it towers over the scene. His swirl of fine pencil marks suggests the wind is building, gusting around the tiny figures as they struggle to secure the hay they need to see their livestock through the coming winter.