The atmospheric modelling activities in SPL have a heritage of more than two decades. SPL made a humble beginning in this complex field in the early 1990s through development of an in-house finite element two-dimensional atmospheric boundary layer (ABL) model, which was able to simulate the offshore and onshore structure of the coastal ABL over Thumba, and the evolution of thermal internal boundary layer (TIBL). In the late 1990s, SPL ventured into the adoption, installation and utilisation of a non-hydrostatic advanced regional prediction system (ARPS) model for the Indian region, which had the capability of prediction of severe weather events for a mesoscale domain. The ARPS model was extensively used in research mode for investigating the topography-induced features over Thumba coast by introducing an artificial bell-shaped mountain in the model topography. Having attained sufficient experience in handling the mesoscale atmospheric models, SPL further expanded its wings in the field of regional and global atmospheric/climate modelling through utilisation of various numerical atmospheric models (e.g., HRM, COSMO, WRF, RegCM, to name a few) for addressing some important aspects pertaining to the prediction of weather and climate system of the planet Earth. During the period of this report, the numerical atmospheric modelling activities attained the status of a new science branch within the SPL.