As a replacement of the 1949 primary training manual for supplementary aeronautical weather reports, instructions are presented in this Training Paper No. 5 for the purpose of guiding learners through their study of the Weather Service Observing Handbook (WSOH) No. 4. The content is divided into six chapters concerned with such topics as introduction to aviation weather observation, sky conditions, ceiling heights, sky cover, obscuring phenomena, visibility, atmospheric phenomena, temperatures and dewpoint, and wind. Each chapter includes a reading assignment corresponding to the WSOH No. 4 content, a detailed discussion section, and a set of review questions with answers. Emphases are placed on the use of trained encoding skills to take and record surface SAWRS observations. Included are a meteorological form 1-10C, illustrations for explanation purposes, ceiling designators for layers aloft, a sample visibility chart, and summaries of sky condition, visibility, temperature data, weather, and obstruction-to-vision entries. (CC)