Air temperature, barometric pressure, and humidity in the upper atmosphere can be measured by instruments inside a radio sound box that is carried into the air by balloon. The measurements are carried back to earth by a radio transmitter in the box. Radar is used to track hurricanes and tornadoes through a network of weather stations throughout the United States. These data are used to provide early warning to residents that are in the paths of tornadoes and hurricanes.

This program introduces radar-tracking of storms with a filmed sequence of a time lapse PPI (plan position indicator) scope view of a hurricane. Dr. George Benton, Johns Hopkins University professor of meteorology, describes the origins of radar (an acronym for radio detection and ranging) and how it works. First used to detect and track airplanes, radar now locates clouds and precipitation. Dr. Benton compares echoes from 1 cm, 10 cm, and 23 cm wavelength radar sets used to detect various types of weather. Captain Howard Orville, meteorologist consultant for Bendix-Freeze Corp. in Baltimore, lists some of the milestones in radar history: 1922, A. Hoyt Taylor was one of the inventors of radar; 1941, the first hailstorm was tracked; and 1944, the first eye of a hurricane was tracked. He stresses the importance of radar in meteorology and displays the tracks of hurricanes Diane, Connie, and Audrey on a map. Dr. Benton describes types of storms and the amount of warning time radar can provide.