Some have been trained to aviod large supercell-type thunderstorms in the belief that this will prevent encounters with microbursts. A microburst is a small, very intense downdraft that descends to the ground resulting in a strong wind divergence. Some microbursts can pose a threat to life and property, but all microbursts pose a significant threat to aviation. https://www.youtube.com/embed/HDfodeURad0#t=26