Forecasting of thunderstorms in the pre-monsoon season at Delhi

Of all the phenomena in the atmosphere, there is none that exceeds the thunderstorm in beauty as it builds up from a small detached cumulus into a towering and awe-inspiring cumulonimbus. However, aviators treat thunderstorms with reverence for they are associated with hail, wind shear and turbulence, squalls and at times heavy precipitation. Thunderstorms during the hot and dry pre-monsoon season over north-west India can lead to duststorms, which reduce the visibility to such low values (almost nil) that it is dangerous for any outdoor human activity to take place. Squalls and hail can damage the crops, high-rise structures and uproot trees etc., and the associated turbulence can produce a severe gust load on aircraft which can seriously jeopardise flight safety. The duration of a storm is usually between half an hour to one hour, though on some occasions it may continue for several hours. Thus, prior knowledge of the occurrence of thunderstorms on a time scale varying between an hour to a few hours before the event is very useful for aviation as well as other activities such as transportation, agriculture and construction.