A tornado is a violently rotating column of air which is in contact with both a cumulunimbus cloud,or in rare cases,a cumulus cloud base and the surface of the earth. Tornadoes come in many sizes but are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris. Tornadoes oftej develop from a class of thunderstorms known as supercells contain mesocyclones ,an area an organized rotation a few miles up in the atmosphere,usually 1-6 miles across. Most intense tornadoes develop from supercelss. in addition to tornadoes, very heavy rain,frequent lightning,strong wind gust,and hail are common in such storms. Most tornadoes from supercells from supercells follow a recognizable life cycle. that begins when increasing rainfall drags with it in area of quickly descending air known as the rear flank downdraft.This downdraft accelerates as it approaches the ground, and drags the supercells rotating mesocyclone towards the ground with it.