This study investigates the climatology of Convective Available Potential Energy (CAPE) over Bangladesh and its eight administrative divisions, along with three lightning hotspots (Sherpur, Shahjadpur, and Bajitpur), using monthly, seasonal, and annual data for 40 years (1982–2021). The monthly CAPE data at 0000 UTC and 1200 UTC has been collected from the fifth generation of the European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis data (ERA5) at 0.25° resolution. The study reveals that the increasing CAPE trend over Bangladesh may be responsible for the increased frequency of extreme events. Significant CAPE values were observed in Bangladesh’s south-west and southern parts from March to May. In April, there was a notable increasing trend in CAPE values, particularly in the north-western region. The average CAPE values for Bangladesh’s three lightning hotspot regions (Sherpur, Shahjadpur, and Bajitpur) is higher than 1500 J/kg during the pre-monsoon at 0000 UTC, directly correlating with the lightning and thunderstorm. The Mann-Kendall test has been employed to follow yearly and seasonal trends. Overall, this study provides valuable insights into the spatial distribution of CAPE and its association with thunderstorms in Bangladesh, which can inform the development of effective strategies to manage weather-related hazards in the country.

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Atmospheric turbulence is a primary meteorological hazard to en-route air traffic. The role of Clear Air Turbulence (CAT) for various processes in the atmosphere is still ambiguous. An Air India flight AI462 encountered severe CAT on 19 April 2018. The present study simulates the CAT event and is focused on understanding and investigating favourable conditions for the occurrence of CAT. Weather Research and Forecasting (WRF) Model V4.0.3 has been used to simulate the turbulence. The 6-hourly NCEP FNL Operational Global Analysis data at 0.25° X 0.25° resolution is taken as input to provide the model's initial and lateral boundary conditions. For simulating the atmospheric environments at the time of the event, Yonsei University Scheme, WSM 3-Class Simple Ice Scheme, Kain-Fritsch (New-Eta) Scheme, Rapid Radiative Transfer Model (RRTM) Scheme, and Revised MM5 Monin-Obukhov Scheme are used. This study shows that Vertical Velocity, Geopotential Thickness, Wind Shear and Bulk Richardson Number Shear are correlated with CAT as the model predicted both upward and downward velocity very close to each other between 400 hPa and 550 hPa levels along with strong geopotential thickness gradient and strong wind shear gradient near the accident location. This could lead to CAT. Model simulated variations in CAT Index with change in time and pressure levels. CAT dissipates as we go higher in the atmosphere above 550 hPa.