This book is primarily meant for professional trainee pilots of all categories as prescribed by DGCA (Director General of Civil Aviation) and particularly for Commercial Pilots Licence (CPL) and Airlines Transport Pilots Licence. The book covers Atmosphere Weather elements Atmospheric Density Water in the atmosphere Atmospheric processes Winds and Atmospheric circulation Global patterns of pressure, temperature, wind Clouds and Precipitation Air masses and fronts Aviation weather reports Broadcast of weather reports. Salient features · Covers the whole range of syllabus of all categories of pilot courses prescribed by DGCA, particularly CPL, ATPL, the ultimate courses. · As per the examination system of DGCA, multiple Choice (objective) questions with answers (about 1300) have been provided at the end of each chapter. · Also provided a miscellaneous Question Bank at the end of the book. · World Area Forecasts such as grid point data in digital and numerical form, prognostic charts of significant weather, SIGMET information, VOLMET Broad Cast are described sufficiently. · Meteorological observations consists of units of measurement, observatory set up, automatic weather observing system are covered. · Brief description of weather satellites, IMD Meteorological Data Processing system are given. · Aviation weather reports and Forecasts codes have been given which were evolved by WMO in consultation with ICAO. ·Great care has been taken to explain each term of the code METAR, SPECI, CODAR, WINTEM Reports and TAF, ARFOR, ROFOR forecasts.