Study of statistical estimated parameters using ERA5 reanalysis data over Khulna region during monsoon season

Thunderstorms are extreme localized weather phenomena that form primarily as a result of intense atmospheric convection. These are characterized by heavy rainfall, lightning and thunder. Thunderstorms occur in monsoon season over some parts of the world, and they can be found in the rain bands of many convective systems. Thunderstorms are a natural weather occurrence that results in significant damage to property and people all over the world. Lifted index, K index, total totals index, humidity index (HI), total precipitable water (TPW), convective available potential energy, deep convective index, S index, maximum temperature and rainfall parameters are investigated over Khulna region in Bangladesh during the monsoon season. We have measured all the above parameters using daily ERA5 reanalysis data for the monsoon season from 2011 to 2020. High TPW values (~ > 60 mm) and low HI values (~ < 20 K) are observed during July and August months over Khulna region. DCI values greater than 30 °C are observed which indicates highly favorable for severe convection-related thunderstorms. We have experimented ARMA model to estimate four parameters. The major motive behind this is to compare the accuracy of the ARMA model data to ERA5 data. For obtaining reliable statistical estimates of thunderstorm parameters, the ARMA model proved to be extremely useful.