Lectures in Meteorology is a comprehensive reference book for meteorologists and environmental scientists to look up material on the thermodynamics, dynamics and chemistry of the troposphere. The lectures demonstrate how to derive/develop equations – an essential tool for model development. All chapters present application of the material including in numerical models. The lectures are written in modular form, i.e. they can be used at the undergraduate level for classes covered by the chapters or at the graduate level as a comprehensive, intensive course. The student/instructor can address chapters 2 (thermodynamics) and 4 (radiation) in any order. They can also switch the order of chapter 5 (chemistry) and 6 (dynamics). Chapter 7 (climatology) needs the understanding of all chapters. Chapter 3 (cloud physics) needs basics from chapter 2 to understand the cloud microphysical processes. The governing conservation equations for trace constituents, dry air, water substances, total mass, energy, entropy, and momentum are presented including simplifications and their application in models. Basic principles of climatology discussed include analysis methods, atmospheric waves and their analytical solutions, tropical and extra-tropical cyclones, classical and non-classical mesoscale circulations, and the global circulation. The atmospheric chemistry part encompasses photolytic and gas-phase processes, aqueous chemistry, aerosol processes, fundamentals of biogeochemical cycles and the ozone layer. Solar and terrestrial radiation, major absorbers, radiation balance, radiative equilibrium, radiative-convective equilibrium, basics of molecular, aerosol, and cloud adsorption and scattering and their use in remote sensing are presented.