Variability and Trends in the Thermodynamic Indices over Eastern India Associated with Pre-monsoon Thunderstorm Variability

Abstract

The eastern Indian region encounters severe thunderstorms during pre-monsoon season every year. As these thunderstorms are known for their association with catastrophic destruction of properties, lives, and economy, the prediction of these thunderstorms is widely attempted over the years. Thermodynamic indices, being one important aspect of analysing these thunderstorms, are able to show the changes associated with thunderstorms over different stations, as well spatially over the region. However, a detailed investigation regarding the variability and trends in these thermodynamic indices needs to be explored, to understand, if there is an underlying repeatability in the progression of these events over the Eastern India. The present study attempts to study the variability and trends in Thermodynamic Indices during pre-monsoon season over the eastern India using surface information about thunderstorms, radiosonde data, satellite (TRMM daily rainfall) data and reanalysis data sets (ERA5) for 1987-2025. The study will attempt to identify the reasons behind any noticed variability or trends in these indices and will explore the possibilities of changing the frequencies of thunderstorms association with the observed results over the region.