Timelapse footage of the downburst (right) and rain-free updraft (left) regions of a thunderstorm cell. The updraft is the region that powers the storm, driven by low pressure at its centre. The moist rising air is carried upwards and cools and the moisture precipitates, falling as rain. This cools the air around it, causing it to become denser and sink rapidly to the ground, forming the wet downburst. Filmed in the USA on a summer afternoon.