Multiple large-scale monsoonal weather systems created conditions for mesoscale convective activity over Delhi NCR, resulting in intense thunderstorms and heavy rainfall during the early hours of June 28, the India Meteorological Department said.
This activity was supported by thermodynamic instability in the atmosphere, which is favourable for thunderstorms, it said in a statement explaining the reason for the record rainfall that brought India's national capital to its knees.
The India Meteorological Department (IMD) said the monsoon was stalled over eastern India for an extended period due to weak monsoon currents over the Bay of Bengal. From June 25 onwards, the monsoon currents strengthened with the development of an upper air cyclonic circulation over the central and northern Bay of Bengal at middle atmospheric levels.
At the same time, the Southwest Monsoon currents over the Arabian Sea intensified, with increased wind speeds and the strengthening of the offshore west coast .
