Essay on the Stages in the development of a Thunderstorm

Different stages in the development of a thunderstorm. Generally a thunderstorm has 3 to 5 cells, each of which goes through a life cycle. In the life cycle of a cell there are three distinct stages determined by the magnitude and direction of the ascending or descending air currents. These stages are as follows:-

1. Cumulus stage:

In the cumulus stage there is an updraft throughout the cell. The cloud contains precipitation particles. As the cloud grows larger in size, the updrafts become stronger and more widespread.

These updrafts sometimes acquire speeds of 160 km per hour so that they are able to uphold the large hailstones aloft. In the upper parts of the cloud, large quantities of liquid water particles and ice crystals co-exist, a fact which initiates the downdraft.

2. Mature stage:

The stage of maturity is marked by strong updrafts and downdrafts in the cloud. Heavy precipitation falls on the ground. The frictional drag exerted by precipitation, according to Byers, changes the updraft into a downdraft which continues further on its own.

The falling of precipitation and the beginning of downdrafts take place simultaneously. It is to be pointed out that at maturity the upper parts of the cloud are characterized by updrafts and the lower parts, on the other hand, have more pronounced downdrafts.

The severity of thunderstorm is at its peak. Maximum of lightning and thunder is seen in this stage. Weather at the surface is characterized by heavy rainfall and high velocity winds. The most severe turbulence, often a weather hazard to flying aeroplanes, marks the weather aloft.

3. Dissipating stage:

The disappearance of updrafts marks the beginning of the dissipating stage. This stage is characterized by weak downdrafts and light rain. Downdraft air spreads on the ground outward.

The out-flowing surface winds are often very gusty and wind velocity is nearly high. Sometimes the downdraft which spreads over the entire area of the cell produces most welcome cooling effect on hot summer days.